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                            SELLERS v. SELLERS
                            Cite as 23 Neb. App. 219




                     Jason Sellers, appellant, v.
                     Stephanie Sellers, appellee,
                       and State of Nebraska,
                         intervenor-appellee.
                                ___ N.W.2d ___

                    Filed September 1, 2015.   No. A-14-665.

 1.	 Modification of Decree: Child Support: Appeal and Error. An appel-
     late court reviews proceedings for modification of child support de novo
     on the record and will affirm the judgment of the trial court absent an
     abuse of discretion.
 2.	 Judges: Words and Phrases. A judicial abuse of discretion exists when
     reasons or rulings of a trial judge are clearly untenable, unfairly depriv-
     ing a litigant of a substantial right and denying just results in matters
     submitted for disposition.
 3.	 Child Support: Rules of the Supreme Court. Interpretation of the
     Nebraska Child Support Guidelines presents a question of law.
 4.	 Judgments: Appeal and Error. An appellate court resolves questions
     of law independently of the lower court’s conclusion.
 5.	 Rules of Evidence. In proceedings where the Nebraska Evidence Rules
     apply, the admissibility of evidence is controlled by the Nebraska
     Evidence Rules; judicial discretion is involved only when the rules make
     discretion a factor in determining admissibility.
 6.	 Judges: Evidence: Appeal and Error. The exercise of judicial discre-
     tion is implicit in determining the relevance of evidence, and a trial
     court’s decision regarding relevance will not be reversed absent an abuse
     of discretion.
 7.	 Modification of Decree: Child Support: Proof. A party seeking to
     modify a child support order must show a material change in circum-
     stances which (1) occurred subsequent to the entry of the original decree
     or previous modification and (2) was not contemplated when the decree
     was entered.
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 8.	 Courts: Child Support. The trial court has discretion to choose whether
     and how to calculate a deduction for subsequent children.
 9.	 Child Support. No precise mathematical formula exists for calculating
     child support when subsequent children are involved, but the court must
     perform the calculation in a manner that does not benefit one family at
     the expense of the other.
10.	 Modification of Decree: Child Support: Proof. The party requesting a
     deduction for his or her obligation to support subsequent children bears
     the burden of providing evidence of the obligation, including the income
     of the other parent of the child.
11.	 Child Support: Appeal and Error. A party may raise two separate
     issues on appeal when a trial court allows a deduction for the obligor’s
     support of subsequent children: (1) whether the court abused its discre-
     tion by allowing a deduction and (2) whether the court’s method of
     calculation was an abuse of discretion.
12.	 Records: Appeal and Error. An appellate brief generally may not
     expand the evidentiary record and should limit itself to arguments sup-
     ported by the record.
13.	 Child Support: Appeal and Error. Whether a child support order
     should be retroactive is entrusted to the discretion of the trial court, and
     an appellate court will affirm its decision absent an abuse of discretion.
14.	 Child Support. In determining whether to order retroactive support, a
     court must consider the parties’ status, character, situation, and attendant
     circumstances. As part of that consideration, the court must consider
     whether the obligated party has the ability to pay the lump-sum amount
     of a retroactive award.
15.	 Modification of Decree: Child Support: Time. Absent equities to the
     contrary, modification of a child support order should be applied ret-
     roactively to the first day of the month following the filing date of the
     application for modification.
16.	 Child Support: Child Custody. In the determination of child support,
     the children and the custodial parent should not be penalized by delay in
     the legal process, nor should the noncustodial parent gratuitously benefit
     from such delay.
17.	 Evidence: Words and Phrases. Relevant evidence means evidence
     having any tendency to make the existence of any fact that is of conse-
     quence to the determination of the action more probable or less probable
     than it would be without the evidence.
18.	 Trial: Evidence: Appeal and Error. Upon a de novo review in an
     appellate court, incompetent, irrelevant, and immaterial evidence offered
     in the original trial, which was admitted over proper objections by the
     adverse party, will be disregarded.
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         Decisions of the Nebraska Court of A ppeals
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

  Appeal from the District Court for Lincoln County: R ichard
A. Birch, Judge. Affirmed.

  Monelle M. Nichols, of Nichols Law, for appellant.

  Stephanie Sellers, pro se.

   Claudine K. Thorne, Deputy Lincoln County Attorney, for
intervenor-appellee.

  Moore, Chief Judge, and Pirtle and Bishop, Judges.

   Moore, Chief Judge.
                      I. INTRODUCTION
   Jason Sellers appeals from the order of the district court for
Lincoln County, which modified his child support obligation
to Stephanie Sellers, also known as Stephanie Rodriguez, for
the support of the parties’ minor children. Because we find no
abuse of discretion in the court’s modification of Jason’s child
support, we affirm.

                      II. BACKGROUND
   Jason and Stephanie were married in February 2001 and are
the parents of three minor children. In March 2010, the dis-
trict court dissolved Jason and Stephanie’s marriage, awarded
Stephanie custody of the parties’ children, and ordered Jason
to pay child support of $96 per month. Jason was incarcerated
at the time the decree was entered.
   In March 2013, Stephanie requested a review of Jason’s
child support, pursuant to Neb. Rev. Stat. § 43-512.12 (Cum.
Supp. 2014), which provides for a review by the Nebraska
Department of Health and Human Services (Department) “in
cases in which a party has applied for services under Title
IV-D of the federal Social Security Act . . . to determine
whether to refer such orders to the county attorney or autho-
rized attorney for filing of an application for modification.”
Jason failed to provide adequate financial information to the
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

Department, creating a rebuttable presumption that there had
been a material change in his financial circumstances such that
his child support obligation should be increased. See Neb. Rev.
Stat. § 43-512.14 (Reissue 2008).
   On December 11, 2013, following a review by the
Department’s “Review and Modification Unit,” the State of
Nebraska filed a complaint for modification of child sup-
port, requesting an increase in Jason’s monthly child support
obligation based on a change in circumstances to an amount
consistent with the Nebraska Child Support Guidelines.
Jason was personally served with the complaint on January
21, 2014.
   After three continuances, two of which were at Jason’s
request, a modification hearing was held before the district
court on June 17, 2014.
   At the time of the modification hearing, Jason lived with his
current wife, their 1-year-old son, and his 5-year-old stepson.
Jason has been involved in his stepson’s life since his birth
and is the only father this child has ever known. Jason’s wife
is a stay-at-home mother.
   At the time of the decree in March 2010, Jason was incar-
cerated for assault. The district court overruled Jason’s rel-
evance objection to the reason for his incarceration. Jason was
released from prison in June 2010. Jason is now employed at a
company where he earns $16.12 per hour and works 40 hours
per week. He contributes to a retirement account through his
employment at a rate of 4 percent. Jason has health insurance
available to him through his employment, which insurance he
provides for himself and his children. To provide this health
insurance for the three minor children in this case, Jason pays
an additional $135 per month above what it costs him to pro-
vide health insurance for himself.
   Jason has been diagnosed with diverticulitis, and he testi-
fied about his costs for medication and surgeries resulting
from the condition. Jason underwent three surgeries in the
year prior to the hearing. According to Jason, his medical
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

providers have told him that the issues that led to his second
and third surgeries could happen again and that it was “[j]ust
a matter of time.” Jason testified that over the last year, his
medical expenses have been $30,000 or more, which expenses
he believed included the cost that was covered by health
insurance. Jason offered exhibit 1, which he stated contained
his medical bills for the previous 11⁄2 years. According to a
typewritten summary page included in the exhibit, Jason’s
out-of-pocket medical costs from January through June 2014
were $13,734.29. The State objected to exhibit 1 because
it included several bills for individuals other than Jason.
The district court received exhibit 1 into evidence, stating
that it would not take any irrelevant portions of the exhibit
into account in reaching its decision. Jason testified that he
did not know the limits, deductible, or maximum out-of-
pocket expenses under his health insurance policy, as he did
not pay attention to any such documentation received from
his employer.
   At the time of the modification hearing, Jason was current
on his child support payments. He did not feel he would be
able to pay child support of $712 per month as reflected in
the child support calculation submitted by the State, and he
testified that his ongoing medical bills would make it difficult
for him to pay any amount of retroactive child support. Jason
testified that he could possibly afford child support of $176 as
reflected in one of his child support calculations.
   Stephanie has been a respite provider for the past 5 years,
but at the time of trial did not have current employment in that
capacity because the individual she had been caring for had
been placed in a nursing home. Stephanie earned $11,712 in
2013 and $13,899 in 2012. Stephanie testified that she does
not have an illness or disability that prevents her from working
full time. She receives public assistance in the form of food
stamps, and the parties’ children are covered under Medicaid.
She has also received some assistance from her parents. She
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                     SELLERS v. SELLERS
                     Cite as 23 Neb. App. 219

has a boyfriend who is involved in the children’s lives and
“helps out.”
   Stephanie testified about her understanding of the health
insurance Jason was providing for the children. According
to Stephanie, the insurance became effective April 1, 2014.
Based on documentation she received from the insurance
company and discussion with Jason, Stephanie testified that
the deductible was $4,500 for a family and $2,250 for a per-
son. Stephanie understood the annual out-of-pocket maximum
under the insurance plan was $7,000 for a family and $3,500
per person.
   On June 24, 2014, the district court entered an order modi-
fying Jason’s child support obligation. The court found that
since entry of the divorce decree in March 2010, there had
been a material change in circumstances as a result of the
increase in Jason’s income. The court found that the parties
were in agreement with respect to their income and earning
capacities, and it established Stephanie’s earning capacity
for child support purposes at $1,257 per month and Jason’s
income at $2,794 per month. The court found that Jason
was entitled to a deduction for his retirement contribution,
for the cost of health insurance, and for the support of the
one child of his current marriage. The court set the deduc-
tion for the child of Jason’s current marriage at $234. The
court did not allow a deduction for Jason’s support of his
stepchild. The court noted Jason’s serious medical issues, but
it observed that his actual income from 2013 was in excess
of the amount attributed to him on the parties’ child support
calculations. The court found that any determination that
Jason’s past medical problems would cause a future reduction
in his income would be speculative. In determining that Jason
failed to produce sufficient evidence to rebut the presump-
tion that the child support guidelines should be applied, the
court noted that Jason testified he did not know the amount
of his deductible, that a number of the medical bills Jason
submitted as evidence were for other individuals, that some
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                       SELLERS v. SELLERS
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of the bills were outside the dates within which they were
alleged to have been incurred, and that there was no way to
determine what Jason’s final liability may have been on such
medical bills. The court ordered Jason to pay, commencing
on February 1, 2014, child support of $712 per month for
three children, $597 per month for two children, and $397 per
month for one child. The court also ordered Jason to continue
to maintain health and medical insurance on the minor chil-
dren through his employer if available to him at a reasonable
cost and to pay 63 percent of any uninsured health or medical
expenses for the minor children in excess of $480 per child
per year.

                III. ASSIGNMENTS OF ERROR
   Jason asserts, restated, that the district court erred in (1)
calculating child support with respect to the amount used as
a deduction for regular support for other children, (2) find-
ing insufficient evidence to rebut the strict application of the
guidelines and/or failing to allow a deviation for his medical
expenses, (3) failing to recognize and apply the correct basic
subsistence limitation in calculating child support, (4) enter-
ing a child support order in contradiction of public policy
and legislative intent that would require Jason to seek public
assistance, (5) ordering the payment of retroactive support, (6)
allowing evidence of the reason for Jason’s previous incarcera-
tion, (7) ordering Jason to pay for 63 percent of the unreim-
bursed health care costs, and (8) denying Jason’s application
to proceed in forma pauperis.

                 IV. STANDARD OF REVIEW
   [1,2] An appellate court reviews proceedings for modifica-
tion of child support de novo on the record and will affirm
the judgment of the trial court absent an abuse of discretion.
Schwarz v. Schwarz, 289 Neb. 960, 857 N.W.2d 802 (2015). A
judicial abuse of discretion exists when reasons or rulings of
a trial judge are clearly untenable, unfairly depriving a litigant
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

of a substantial right and denying just results in matters sub-
mitted for disposition. Id.
   [3,4] Interpretation of the Nebraska Child Support Guidelines
presents a question of law. Schwarz v. Schwarz, supra. An
appellate court resolves questions of law independently of the
lower court’s conclusion. Id.
   [5,6] In proceedings where the Nebraska Evidence Rules
apply, the admissibility of evidence is controlled by the
Nebraska Evidence Rules; judicial discretion is involved only
when the rules make discretion a factor in determining admis-
sibility. Griffith v. Drew’s LLC, 290 Neb. 508, 860 N.W.2d
749 (2015). The exercise of judicial discretion is implicit in
determining the relevance of evidence, and a trial court’s deci-
sion regarding relevance will not be reversed absent an abuse
of discretion. Id.

                          V. ANALYSIS
                 1. Child Support Calculation
   [7] A party seeking to modify a child support order must
show a material change in circumstances which (1) occurred
subsequent to the entry of the original decree or previous
modification and (2) was not contemplated when the decree
was entered. State on behalf of B.M. v. Brian F., 288 Neb. 106,
846 N.W.2d 257 (2014). The modification proceedings in this
case were initiated after Stephanie’s request for a review by the
Department, and Jason’s failure to provide adequate financial
information created a rebuttable presumption that his income
had changed from the time of the decree. See §§ 43-512.12
and 43-512.14.
   The district court found a material change in circumstances
and modified Jason’s child support obligation, increasing it
from $96 to $712 per month for three children. In doing so,
the court established Stephanie’s earning capacity for child
support purposes at $1,257 per month and Jason’s income
at $2,794 per month. It found that Jason was entitled to
deductions for his retirement contribution, the cost of health
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

insurance, and $234 in support for the child of his current
marriage. The court did not allow a deduction for Jason’s step-
child or a deviation in light of his medical expenses. Although
Jason asserts that the district court erred in calculating his
child support obligation, he does not dispute that his income
has increased since entry of the divorce decree, and he does
not assign error to the income amounts used by the court in
its calculation. He specifically assigns error to the amount
used by the court as a deduction for regular support for other
children, the court’s finding insufficient evidence to rebut the
strict application of the guidelines and/or failure to allow a
deviation for his medical expenses, and the court’s failure to
recognize and apply the correct basic subsistence limitation in
calculating child support. He also asserts that the court erred
by entering a child support order that would require him to
seek public assistance. We address each of these arguments
separately below.

                     (a) Regular Support for
                          Other Children
   The district court allowed a deduction of $234 per month for
Jason’s subsequently born child. The Nebraska Child Support
Guidelines allow for a deduction for biological or adopted
children for whom the obligor provides regular support. Neb.
Ct. R. § 4-205(E). Jason argues that his stepchild should
have also been taken into account in this deduction. Although
Jason’s support of this child is to be commended, there is no
provision in the guidelines that would allow a deduction for a
child other than a biological or adopted child.
   [8-11] Jason also takes issue with the manner in which the
trial court calculated the deduction for his subsequent child.
The trial court has discretion to choose whether and how
to calculate a deduction for subsequent children. Schwarz v.
Schwarz, 289 Neb. 960, 857 N.W.2d 802 (2015). No precise
mathematical formula exists for calculating child support
when subsequent children are involved, but the court must
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                       SELLERS v. SELLERS
                       Cite as 23 Neb. App. 219

perform the calculation in a manner that does not benefit one
family at the expense of the other. Id. The party requesting
a deduction for his or her obligation to support subsequent
children bears the burden of providing evidence of the obliga-
tion, including the income of the other parent of the child. Id.
A party may raise two separate issues on appeal when a trial
court allows a deduction for the obligor’s support of subse-
quent children: (1) whether the court abused its discretion by
allowing a deduction and (2) whether the court’s method of
calculation was an abuse of discretion. Id.
   In this case, the district court considered Jason’s income
alone and what his obligation would be for his four biologi-
cal children and divided that total obligation by four to arrive
at an amount per child. The deduction of $234 per month for
the subsequently born child was used in the State’s child sup-
port calculation. The State argues that this formula treats all
of Jason’s children fairly and does not provide a benefit to
either his previous children or his subsequently born child.
We agree.
   The calculation adopted by the district court treats all
of Jason’s biological children nearly identically. The court
awarded child support of $712 per month for three children,
based upon the child support guidelines, which represents
25.48 percent of Jason’s gross income of $2,794, or 8.49
percent per child. The deduction of $234 for the child of
his current marriage represents 8.38 percent of Jason’s gross
income. The district court did not abuse its discretion in
calculating the deduction allowed for Jason’s subsequently
born child.

                        (b) Deviation for
                       Medical Expenses
   Jason asserts that the district court erred in finding insuf-
ficient evidence to rebut the strict application of the guidelines
and/or failed to allow a deviation for his medical expenses.
Neb. Ct. R. § 4-203 (rev. 2011) provides in part:
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

         The child support guidelines shall be applied as a
      rebuttable presumption. All orders for child support
      obligations shall be established in accordance with the
      provisions of the guidelines unless the court finds that
      one or both parties have produced sufficient evidence
      to rebut the presumption that the guidelines should
      be applied.
Section 4-203(A) allows for a deviation “[w]hen there are
extraordinary medical costs of either parent or child.” Jason
argues that diverticulitis is a costly and serious medical con-
dition which warranted relief from the strict application of
the guidelines.
   At the modification hearing, Jason testified about the three
surgeries he underwent in the year prior to the modification
hearing due to his diverticulitis diagnosis and testified that
the issues that led to his second and third surgeries could
recur in time. Jason did not present any medical testimony
about the nature of his condition, what future problems are
likely to occur, or the day-to-day ongoing medical expenses
associated with it, extraordinary or otherwise. He testified
that he had incurred medical expenses in the previous year
totaling over $30,000 or more. He acknowledged, however,
that this amount included what was covered by his health
insurance. According to the summary page of exhibit 1, Jason
incurred uncovered medical expenses totaling $13,734.29 in
the first 6 months of 2014. We note, as did the district court,
that exhibit 1 includes bills for individuals other than Jason
and outside of the 6-month period purportedly covered by
the summary page. Jason was unsure about the limits of his
health insurance policy, including the amount of his deduct-
ible and maximum out-of-pocket expenses. He testified that
the health insurance he carried for himself was the same as
what he provided for the children in this case. Stephanie testi-
fied, based on conversations with Jason and information she
received from the insurance company, about the health insur-
ance policy limits, including a family deductible of $4,500,
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                       SELLERS v. SELLERS
                       Cite as 23 Neb. App. 219

individual deductible of $2,250, annual family out-of-pocket
maximum of $7,000, and annual individual out-of-pocket
maximum of $3,500. The court also received into evidence
documentation from the health insurance company of the
policy limits.
   The district court noted that Jason has had serious medi-
cal issues that have affected his health, but it observed that
his actual income from 2013 exceeded the amount attributed
to him in the parties’ proposed child support calculations.
The court concluded that there was no way to determine
Jason’s final liability on the medical bills included in exhibit 1.
Accordingly, the court concluded that Jason failed to present
sufficient evidence to rebut the presumption that the child sup-
port guidelines should be applied. We agree. There is conflict-
ing evidence in the record about Jason’s medical expenses and
nothing beyond speculation to show what his future medical
expenses might be. Because Jason did not present sufficient
evidence to support a deviation for extraordinary medical
expenses, the court did not abuse its discretion in declining to
allow such a deviation.

                (c) Basic Subsistence Limitation
   Jason asserts that the district court erred in failing to rec-
ognize and apply the correct basic subsistence limitation in
calculating child support. Neb. Ct. R. § 4-218 (rev. 2015) cur-
rently provides:
         A parent’s support, child care, and health care obliga-
      tion shall not reduce his or her net income below the
      minimum of $981 [$973 at the time of the modifica-
      tion hearing in this case] net monthly for one person, or
      the poverty guidelines updated annually in the Federal
      Register by the U.S. Department of Health and Human
      Services under authority of 42 U.S.C. § 9902(2), except
      minimum support may be ordered as defined in § 4-209.
   Jason argues that this section expresses two different
basic subsistence limitations. Specifically, he argues that the
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                       SELLERS v. SELLERS
                       Cite as 23 Neb. App. 219

limitation of $973 in place at the time of trial is for one person
while the poverty guidelines updated annually in the Federal
Register based on household size are applicable here. The
State argues that the district court properly applied the limita-
tion of $973 in effect at the time of the modification hearing,
citing to Henke v. Guerrero, 13 Neb. App. 337, 692 N.W.2d
762 (2005).
    This court recently addressed the question of application of
§ 4-218 of the child support guidelines and the proper basic
subsistence limitation to apply when an obligor’s household
consists of more than one person. See Lasu v. Issak, ante p. 83,
___ N.W.2d ___ (2015). In that case, we utilized the poverty
guidelines for the obligor’s entire household as found in the
Federal Register as opposed to the figure for one person as
a starting point in determining the obligor’s child support. In
doing so, we distinguished Henke. We acknowledged that in
Henke, although the father-obligor had another family to sup-
port, this court did not consider the poverty guidelines for his
family of five when reviewing the father’s support obligation,
and instead appeared to utilize the basic subsistence limitation
for one person in determining support for the child at issue in
the paternity action. However, as we discussed in Lasu, the
only assigned error on cross-appeal by the father in Henke was
application of the poverty guidelines with respect to the retro-
active support and the issue of whether to apply the poverty
guideline for one person or for the total household in determin-
ing the child support award was not raised.
    Following our decision in Lasu, we agree with Jason that
it is appropriate to consider the poverty guidelines as updated
in the Federal Register that were in place at the time of this
modification proceeding, pertinent portions of which were
received as exhibit 4. Utilizing the child support calcula-
tion worksheet adopted by the district court, Jason’s monthly
net income is $1,829, after the $234 deduction allowed for
Jason’s subsequently born child. After then subtracting the
child support obligation of $712 as determined by the district
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court, Jason has remaining net monthly income of $1,117.
Using the poverty guideline figure for a household of four
as set forth in exhibit 4, Jason contends that the guide-
lines reflect a monthly limitation of $1,987.50, which greatly
exceeds his actual remaining net monthly income of $1,117.
Thus, Jason asserts that the child support obligation imposed
by the district court violates § 4-218.
   We first note that utilizing the net monthly income for
Jason after giving him credit for his subsequent child and
then in turn considering this child in the household for pur-
poses of the basic subsistence limitation essentially gives
duplicate consideration for the subsequent child. Thus, we
think it appropriate at the outset of our analysis on this issue
to add back the $234 deduction allowed for Jason’s subse-
quently born child in the child support calculation, which
results in a total of $1,351 remaining net income for Jason’s
current household after the child support order of $712
is subtracted.
   In further applying the poverty guidelines as updated annu-
ally in the Federal Register, we are also faced with the ques-
tion of how to determine the household income and size. The
applicable annual update published in the Federal Register and
received into evidence as exhibit 4 in this case states:
         Note that this notice does not provide definitions of
      such terms as “income” or “family,” because there is
      considerable variation in defining these terms among the
      different programs that use the guidelines. These varia-
      tions are traceable to the different laws and regulations
      that govern the various programs. This means that ques-
      tions such as “Is income counted before or after taxes?”,
      “Should a particular type of income be counted?”, and
      “Should a particular person be counted as a member
      of the family/household?” are actually questions about
      how a specific program applies the poverty guidelines.
      All such questions about how a specific program applies
      the guidelines should be directed to the entity that
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      administers or funds the program, since that entity has
      the responsibility for defining such terms as “income” or
      “family,” to the extent that these terms are not already
      defined for the program in legislation or regulations.
   Thus, we determine that for purposes of setting child
support, the questions of how to define income and how
to count a family or household under the poverty guide-
lines as updated annually in the Federal Register should be
determined in a manner consistent with the Nebraska Child
Support Guidelines.
   Jason’s argument regarding § 4-218 focuses only on his
income, as his current wife is not working outside the home.
We note that in Lasu v. Issak, ante p. 83, ___ N.W.2d ___
(2015), both the father and his wife were working, and
thus, we used their combined incomes in applying the pov-
erty guidelines contained in the Federal Register. However,
in considering application of the poverty guidelines as a
mechanism to limit Jason’s child support obligation for his
three prior children in this case, we also consider whether it
is appropriate to impute income to Jason’s current wife. As
mentioned previously, the poverty guidelines update in the
Federal Register does not define “income,” but the Nebraska
Child Support Guidelines recognize that earning capacity may
be considered in lieu of a parent’s actual, present income.
Neb. Ct. R. § 4-204. In applying the child support guidelines,
courts in Nebraska often attribute income to a nonworking
parent in calculating child support. See, e.g., Muller v. Muller,
3 Neb. App. 159, 524 N.W.2d 78 (1994) (no abuse of discre-
tion found where district court attributed income based on
earning capacity to mother who decided not to work to care
for children). On the other hand, in Collins v. Collins, 19 Neb.
App. 529, 808 N.W.2d 905 (2012), we found that the trial
court abused its discretion in imputing minimum-wage earn-
ing capacity to the nonworking mother where the evidence
demonstrated that she could not attain minimum-wage earning
capacity by reasonable efforts.
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

   In this case, both parties attributed earning capacity income
to Stephanie as if she were working full time and earning
minimum wage. Under the circumstances of this case, we
conclude that it is appropriate, in applying the poverty guide-
lines, to likewise attribute earning capacity income to Jason’s
current wife. The only evidence in the record is that she is a
stay-at-home mother; there is no evidence that she could not
attain minimum-wage earning capacity by reasonable efforts.
By also attributing $1,257 gross monthly income to Jason’s
current wife (the same as for Stephanie) and using the trial
court’s worksheet, her net monthly income would be $1,061.
If we add that figure to Jason’s net income of $1,351 (after the
$712 child support is subtracted), we arrive at total household
net monthly income of $2,412, which exceeds the basic sub­
sistence limitation of $1,987.50 for a family of four. For the
sake of completeness, we considered the household size as four
to include Jason’s stepson, since we imputed income to Jason’s
current wife.
   In conclusion, we determine that while it was appropri-
ate for the district court to consider the poverty guidelines
as updated in the Federal Register for Jason’s household, the
district court’s award of child support ultimately did not vio-
late § 4-218.

                        (d) Public Policy
   [12] Jason asserts that the district court erred in entering
a child support order in contradiction of public policy and
legislative intent that would require him to seek public assist­
ance. Much of his argument in support of this assignment
of error focuses on Stephanie’s finances and decisions with
respect to employment or is composed of colorful historical
references. Although his brief states that his pay is now being
garnished to pay child support arrears and that he is trying to
qualify for state assistance, this information is outside of the
record presented on appeal. An appellate brief generally may
not expand the evidentiary record and should limit itself to
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         Decisions of the Nebraska Court of A ppeals
               23 Nebraska A ppellate R eports
                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

arguments supported by the record. Galaxy Telecom v. SRS,
Inc., 13 Neb. App. 178, 689 N.W.2d 866 (2004). To the extent
that Jason’s arguments relate to his assignments of error
with respect to retroactive support, the correct basic subsist­
ence limitation, and his requested deviation for his medical
expenses, we have addressed those arguments elsewhere in
this opinion. This assignment of error is without merit.

                   (e) Conclusion Regarding
                         Child Support
   The district court did not abuse its discretion in determin-
ing Jason’s child support obligation for the children at issue in
this case.

                  2. R etroactive Modification
   Jason asserts that the district court erred in ordering the
payment of retroactive support. The complaint for modi-
fication in this case was filed in December 2013, and a
modification hearing was initially scheduled for February
18, 2014. The hearing, however, was continued three times
before finally occurring on June 17. The first continuance
was at the State’s request to allow for the required 30 days
between the time Jason was personally served with the com-
plaint on January 21 and the hearing. Two additional continu-
ances were granted at Jason’s request, the first because Jason
was undergoing a medical procedure and the second because
Jason’s counsel needed time to determine whether there was a
conflict with her representation of Jason. The court made the
modification of Jason’s child support obligation retroactive to
February 1, 2014.
   [13-16] Whether a child support order should be retroactive
is entrusted to the discretion of the trial court, and an appel-
late court will affirm its decision absent an abuse of discre-
tion. Freeman v. Groskopf, 286 Neb. 713, 838 N.W.2d 300
(2013). In determining whether to order retroactive support,
a court must consider the parties’ status, character, situation,
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

and attendant circumstances. McDonald v. McDonald, 21 Neb.
App. 535, 840 N.W.2d 573 (2013). As part of that consid-
eration, the court must consider whether the obligated party
has the ability to pay the lump-sum amount of a retroactive
award. Id. Absent equities to the contrary, modification of a
child support order should be applied retroactively to the first
day of the month following the filing date of the application
for modification. Id. In the determination of child support, the
children and the custodial parent should not be penalized by
delay in the legal process, nor should the noncustodial parent
gratuitously benefit from such delay. Id.
   Jason argues that an award of retroactive support will not
allow him to meet his child support obligation to the children
in this case and support his new family. Jason argues further
that the district court should have also taken his extensive
medical expenses into consideration. He agrees, however, that
February 1, 2014, was the correct date for any retroactive
award, given that he was not served with notice of the com-
plaint until January 21.
   As discussed above, there was conflicting evidence about
Jason’s uncovered medical expenses and no evidence to show
the extent of any ongoing future medical expenses. The court
did take Jason’s medical expenses into consideration in mak-
ing the award retroactive to February 2014 rather than January.
Under the circumstances of this case, we find no abuse of dis-
cretion in the court’s award of retroactive support.

                   3. Evidence of Previous
                        Incarceration
   [17,18] Jason asserts that the district court erred in allow-
ing evidence of the reason for his previous incarceration.
He argues that he was unfairly prejudiced by the admission
of this evidence. Relevant evidence means evidence having
any tendency to make the existence of any fact that is of
consequence to the determination of the action more prob-
able or less probable than it would be without the evidence.
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         Decisions of the Nebraska Court of A ppeals
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                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

Griffith v. Drew’s LLC, 290 Neb. 508, 860 N.W.2d 749
(2015). Neb. Rev. Stat. § 27-402 (Reissue 2008) provides in
part that “[e]vidence which is not relevant is not admissible.”
“Although relevant, evidence may be excluded if its proba-
tive value is substantially outweighed by the danger of unfair
prejudice . . . .” Neb. Rev. Stat. § 27-403 (Reissue 2008). The
fact of Jason’s incarceration at the time of the decree was
relevant to show that there had been a change in his financial
circumstances warranting a modification of his child support
obligation. While the reason for his incarceration was not
relevant to that determination, we see no evidence that the
district court placed undue emphasis on or even considered
that fact in making its determination with respect to child
support. Further, upon a de novo review in an appellate court,
incompetent, irrelevant, and immaterial evidence offered in
the original trial, which was admitted over proper objections
by the adverse party, will be disregarded. Coffey v. Coffey, 11
Neb. App. 788, 661 N.W.2d 327 (2003). We have disregarded
the reason for Jason’s incarceration in our de novo review.
This assignment of error is without merit.

                   4. Unreimbursed Health
                          Care Costs
   Jason asserts that the district court erred in ordering him
to pay for 63 percent of the unreimbursed health care costs.
He does not separately argue this assignment of error, only
mentioning it as error in connection with his arguments about
the correct basic subsistence limitation and award of retroac-
tive support which we have already addressed above. Jason’s
assertions about unreimbursed health care costs amount to an
argument that he cannot afford to pay the award of 63 percent.
   Neb. Ct. R. § 4-215(B) (rev. 2011) states in relevant part:
“All nonreimbursed reasonable and necessary children’s health
care costs in excess of $480 per child per year shall be
allocated to the obligor parent as determined by the court,
but shall not exceed the proportion of the obligor’s parental
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         Decisions of the Nebraska Court of A ppeals
               23 Nebraska A ppellate R eports
                      SELLERS v. SELLERS
                      Cite as 23 Neb. App. 219

contribution (worksheet 1, line 6).” Under the district court’s
calculations in this case, Jason’s proportion of the parental
contribution is 63 percent. We have already found no abuse
of discretion in the court’s child support calculation. We also
note the evidence shows that the children’s medical expenses
are largely covered by Medicaid. Further, there is nothing
in the record to show that the children have any unusual or
extensive medical expenses. Jason has not shown what impact,
if any, the award of 63 percent of the nonreimbursed medical
expenses will actually have on his finances. This assignment
of error is without merit.

                    5. A pplication to Proceed
                        In Forma Pauperis
   Jason asserts that the district court erred in denying his
application to proceed in forma pauperis in prosecuting his
appeal from the June 24, 2014, order. Jason filed his notice of
appeal on July 18, indicating that he was “delay[ing]” deposit
of the docket fee and costs pending a ruling on his in forma
pauperis application. The application to proceed in forma pau-
peris and poverty affidavit was filed on July 22 and was denied
by the district court on that same date. The clerk’s certificate
in our transcript shows that the docket fee was paid on July 18,
and the cash bond was paid on July 22. After the district court
denied Jason’s request to proceed in forma pauperis on July
22, he had 30 days to appeal the ruling or proceed by paying
the docket fee. See, Neb. Rev. Stat. § 25-2301.02(1) (Reissue
2008); Glass v. Kenney, 268 Neb. 704, 687 N.W.2d 907 (2004);
Martin v. McGinn, 265 Neb. 403, 657 N.W.2d 217 (2003).
Because Jason chose to pay the docket fee, he cannot now be
heard to complain of this issue.
                     VI. CONCLUSION
  Because we find no abuse of discretion in the district court’s
modification of Jason’s child support, we affirm.
                                                   A ffirmed.
