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                 Justin S. Furstenfeld, appellant, v.
                       Lisa B. Pepin, appellee.
                                ___ N.W.2d ___

                     Filed August 18, 2015.   No. A-14-814.

 1.	 Records: Appeal and Error. A party’s brief may not expand the record.
 2.	 Appeal and Error. The purpose of an appellant’s reply brief is to
     respond to the arguments the appellee has advanced against the errors
     assigned in the appellant’s initial brief.
 3.	 Waiver: Appeal and Error. Errors not assigned in an appellant’s initial
     brief are thus waived and may not be asserted for the first time in a
     reply brief.
 4.	 Modification of Decree: Appeal and Error. Modification of a dis-
     solution decree is a matter entrusted to the discretion of the trial court,
     whose order is reviewed de novo on the record, and which will be
     affirmed absent an abuse of discretion.
 5.	 Contracts. The construction of a contract is a matter of law, in connec-
     tion with which an appellate court has an obligation to reach an indepen-
     dent, correct conclusion irrespective of the determinations made by the
     court below.
 6.	 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.
 7.	 Rules of Evidence: Appeal and Error. Where the Nebraska Evidence
     Rules commit the evidentiary question at issue to the discretion of the
     trial court, an appellate court reviews the admissibility of evidence for
     an abuse of discretion.
 8.	 Judgments: Words and Phrases. An abuse of discretion occurs when a
     trial court’s decision is based upon reasons that are untenable or unrea-
     sonable or if its action is clearly against justice or conscience, reason,
     and evidence.
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 9.	 Appeal and Error. For an appellate court to consider an alleged error, a
     party must specifically assign and argue it.
10.	 ____. Appellate courts do not generally consider arguments and theories
     raised for the first time on appeal.
11.	 Rules of Evidence. Under Neb. Evid. R. 402, Neb. Rev. Stat. § 27-402
     (Reissue 2008), all relevant evidence is admissible unless there is some
     specific constitutional or statutory reason to exclude such evidence.
12.	 Trial: Evidence. Evidence which is not relevant is not admissible.
13.	 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.
14.	 Trial: Evidence: Appeal and Error. A trial court has the discretion to
     determine the relevancy and admissibility of evidence, and such deter-
     minations will not be disturbed on appeal unless they constitute an abuse
     of that discretion.
15.	 Evidence: Proof. For evidence to be relevant, all that must be estab-
     lished is a rational, probative connection, however slight, between the
     offered evidence and a fact of consequence.
16.	 Attorney and Client: Presumptions: Proof. On the issue of an attor-
     ney’s authority to make statements on behalf of a client, there is a pre-
     sumption that the attorney has authority and that presumption continues
     until the want of such authority is established. The burden of proof of
     such want of authority is upon the party asserting the same.
17.	 Trial: Evidence: Appeal and Error. To constitute reversible error in a
     civil case, the admission or exclusion of evidence must unfairly preju-
     dice a substantial right of a litigant complaining about evidence admitted
     or excluded.
18.	 Attorneys at Law: Witnesses. When a party seeks to disqualify an
     opposing attorney by calling that attorney as a witness, the court must
     strike a balance between the potential for abuse and those instances
     where the attorney’s testimony may be truly necessary to the opposing
     party’s case.
19.	 Attorneys at Law: Testimony: Proof. The party moving to disqualify
     an opposing attorney bears the burden of establishing that the attorney’s
     testimony will be necessary.
20.	 Trial: Attorneys at Law: Witnesses: Evidence. A party seeking to
     call opposing counsel can prove that counsel is a necessary witness by
     showing that (1) the proposed testimony is material and relevant to the
     determination of the issues being litigated and (2) the evidence is unob-
     tainable elsewhere.
21.	 Contracts. A settlement agreement is subject to the general principles of
     contract law.
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22.	 Contracts: Compromise and Settlement. To have a settlement agree-
     ment, there must be a definite offer and an unconditional acceptance.
23.	 Attorney and Client: Compromise and Settlement. The decision to
     settle a lawsuit belongs to the client; because the client bears the risk
     when settling or refusing to settle a dispute, it is the client, not the law-
     yer, who should assess whether the risk is acceptable.
24.	 ____: ____. Although lawyers retain apparent authority to make proce-
     dural and tactical decisions through the existence of the attorney-client
     relationship, a lawyer cannot settle a client’s claim without express
     authority from the client.
25.	 Attorney and Client: Compromise and Settlement: Appeal and
     Error. Disputes over a lawyer’s authority to settle are factual issues to
     be resolved by the trial court, and an appellate court will not set aside
     a trial court’s factual findings regarding settlement disputes unless such
     findings are clearly erroneous.
26.	 Rules of the Supreme Court: Child Support. In general, child sup-
     port payments should be set according to the Nebraska Child Support
     Guidelines.
27.	 Rules of the Supreme Court: Child Support: Stipulations. Stipulated
     agreements of child support are required to be reviewed against the
     Nebraska Child Support Guidelines.
28.	 ____: ____: ____. If the court approves a stipulation which deviates
     from the Nebraska Child Support Guidelines, specific findings giving
     the reason for the deviation must be made.

  Appeal from the District Court for Lancaster County: John
A. Colborn, Judge. Affirmed.

   Matt Catlett, of Law Office of Matt Catlett, for appellant.

  Terrance A. Poppe, Benjamin D. Kramer, and Andrew K.
Joyce, of Morrow, Poppe, Watermeier & Lonowski, P.C.,
L.L.O., for appellee.

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

   Moore, Chief Judge.
                    I. INTRODUCTION
   Lisa B. Pepin filed a complaint to modify the parent-
ing time and support provisions of a decree of dissolution.
During the ensuing litigation, Pepin and her former husband,
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Justin S. Furstenfeld, engaged in settlement negotiations and
Pepin believed an oral settlement agreement had been reached.
Furstenfeld later refused to sign a stipulation memorializ-
ing the oral agreement, and Pepin filed a motion to enforce.
The district court granted Pepin’s motion to enforce, and
Furstenfeld appeals. Finding no merit to Furstenfeld’s argu-
ments, we affirm.

                II. FACTUAL BACKGROUND
   [1] At the outset, we must pause to observe that Furstenfeld’s
brief contains no fewer than 18 separate assertions which
were not annotated to the record presented to this court. He
acknowledges as much at the end of each such statement by
noting the assertion is not in the record. Pepin has objected to
Furstenfeld’s characterization of the factual background of the
case and correctly notes that a party’s brief may not expand
the record. See State v. Patton, 287 Neb. 899, 845 N.W.2d 572
(2014). Within our factual background, we will only include
those facts which are supported by the record presented to
this court.
   In December 2010, Pepin and Furstenfeld’s marriage was
dissolved pursuant to a decree of dissolution. An amended
decree was entered on January 21, 2011. While these decrees
are not in our record, the district court’s order in this proceed-
ing indicates that the initial decree approved the parties’ prop-
erty settlement, custody agreement, and support agreement and
that the amended decree corrected errors in two provisions of
this agreement. On August 30, Pepin filed an amended com-
plaint for modification of the decree, seeking an increase in
Furstenfeld’s child support obligation and a modification or
suspension of his parenting time with the parties’ minor child.
The district court originally set a trial date of May 21, 2012,
for Pepin’s complaint for modification.
   On May 16, 2012, Pepin; Pepin’s attorney, Terrance Poppe;
and Furstenfeld’s attorney, Matt Catlett, met at Poppe’s office
to conduct a telephonic deposition of Furstenfeld. At the
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time, Furstenfeld was residing at an out-of-state rehabilita-
tion facility. Instead of conducting a deposition, however,
the parties, through their attorneys, engaged in settlement
negotiations and an apparent agreement was reached. After
reaching this agreement, Poppe and Catlett jointly contacted
the district court judge to notify the court of the agreement
and to remove the matter from the court’s trial calendar. Poppe
proceeded to prepare a stipulation containing the terms of the
parties’ agreement.
    Furstenfeld refused to sign the stipulation Poppe prepared.
On June 18, 2012, Pepin filed a motion to enforce the settle-
ment agreement. Specifically, her motion stated that she sought
to enforce “the oral agreement reached by the parties on May
21, 2012.” The court held a hearing on Pepin’s motion on April
7, 2014.
    At the hearing, Pepin testified that she attended a meeting
at her attorney’s office on May 16, 2012. During the meet-
ing, Pepin learned from Poppe that Catlett was also present
that day in another conference room within the office; Pepin
did not personally interact with Catlett. At the end of this
meeting, Pepin understood that a solid agreement had been
reached and both attorneys were to call the judge and advise
the court that the matter had been settled. Pepin further tes-
tified that Poppe prepared a stipulation for modification of
decree that same day which was consistent with the terms of
the oral agreement that had been reached earlier in the day.
Over Furstenfeld’s objection, the court received a copy of the
stipulation into evidence.
    The stipulation for modification of decree provided, in per-
tinent part, that Furstenfeld’s child support obligation would
increase to $3,000 per month commencing June 1, 2012. The
stipulation stated that a Nebraska child support calculation
worksheet was attached and incorporated, although the copy
of the stipulation received in evidence did not contain the
worksheet. The stipulation also provided that Furstenfeld’s
obligation to pay 80 percent of employment-related daycare
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expenses would terminate on May 31, 2012; that he would
remain obligated to provide health insurance for the par-
ties’ minor child; and that he would also pay the first $480
of any health care expenses for the minor child which were
not covered by health insurance and 80 percent of those
uncovered expenses thereafter. The stipulation further stated
that the minor child’s image would not be used for any
purpose by Furstenfeld’s band and that the child would not
attend any of Furstenfeld’s concerts without Pepin’s prior
approval. Other provisions included within the stipulation
provided that Furstenfeld would pay $2,500 toward Pepin’s
attorney fees, that certain orders to show cause would be
vacated, and that the parties would not make disparaging or
derogatory comments about the other through various means
of communication.
   Following Pepin’s testimony, Poppe called Catlett as a wit-
ness to testify in order to provide foundation for an e-mail
regarding the oral settlement agreement and to establish that
Catlett and Furstenfeld engaged in communications during the
May 16, 2012, meeting. Catlett objected to being called as a
witness and cited a number of Nebraska authorities which he
believed established that an attorney does not have authority
to bind a client to an agreement simply because the attorney
had been retained by the client. The court overruled the objec-
tion and permitted Pepin to question Catlett on a limited basis.
After determining it would allow Catlett to testify, the court
permitted Furstenfeld to obtain other counsel. Furstenfeld
elected to represent himself.
   Catlett acknowledged that on May 15, 2012, he sent
an e-mail to Poppe which contained the terms on which
Furstenfeld offered to settle the case. The next day, Catlett
arrived at Poppe’s office to conduct a telephonic deposition
of Furstenfeld. Catlett confirmed that settlement negotiations
ensued, an agreement was reached, and he and Poppe con-
tacted the court to inform it that the matter had been set-
tled. Later that day, Catlett received an e-mail from Poppe’s
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assistant which stated that it included the stipulation for modi-
fication of decree based on the agreement reached that morn-
ing. The e-mail further stated that Poppe would “work up” a
child support calculation that “matches” the $3,000 figure to
attach to the stipulation. Catlett sent the following response to
Poppe’s assistant:
         I believe this accurately reflects the agreement. I’ll
      send to [Furstenfeld], and once he returns to me the
      executed original, I will get it to [Poppe]. The trial date
      has been removed from the judge’s calendar, so we’re not
      under a rush, although I think we told the judge we’d get
      it to him for approval by the end of next week. Neither
      party will need to appear since we’re not changing cus-
      tody or parenting time.
During his testimony, Catlett also stated that he could not
remember whether the attachment to the e-mail was the same
document he was reviewing during his testimony. Catlett fur-
ther remarked that he recalled certain aspects of the stipulation,
but did not recall others. However, he did not have any reason
to believe that the proposed stipulation entered into evidence
was not the same document which was attached to the e-mail
on May 16, 2012.
   On cross-examination, Catlett stated that his client had
not given him the right to sign off on anything. Later in
the hearing, Furstenfeld testified that he did not authorize
Catlett to make the settlement offer contained in the May 15,
2012, e-mail.
   On July 31, 2014, the district court entered an order find-
ing that the parties had entered into a binding settlement
agreement on May 16, 2012. The court determined that this
agreement unconditionally resolved all material terms of the
dispute. The court further found that the proposed stipulation
which had been entered into evidence at the hearing accu-
rately reflected the terms of the parties’ agreement. Finally,
the court approved the terms of the stipulation, finding them
to be fair, reasonable, not unconscionable, and in the best
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interests of the parties’ minor child. The court directed Poppe
to prepare an order consistent with the stipulation, including
child support calculations, for the court’s approval.
   On August 29, 2014, the court signed and filed the order
Poppe prepared. A child support worksheet was attached to
that order.
   Furstenfeld has appealed.

                III. ASSIGNMENTS OF ERROR
   Furstenfeld assigns four errors. He asserts the district court
erred when it (1) received certain exhibits into evidence, (2)
permitted Pepin to call Catlett as a witness, (3) sustained
Pepin’s motion to enforce, and (4) incorporated into its order
a child support calculation worksheet which was unsupported
by evidence.
   [2,3] Furstenfeld also includes an additional assignment
of error in his reply brief. For the first time, he assigns as
error and argues that the district court should not have per-
mitted Pepin to present oral testimony at the hearing. We
will not address this argument because it was not raised in
Furstenfeld’s initial brief. The purpose of an appellant’s reply
brief is to respond to the arguments the appellee has advanced
against the errors assigned in the appellant’s initial brief.
Linscott v. Shasteen, 288 Neb. 276, 847 N.W.2d 283 (2014).
Errors not assigned in an appellant’s initial brief are thus
waived and may not be asserted for the first time in a reply
brief. Id.

                 IV. STANDARD OF REVIEW
   [4] Modification of a dissolution decree is a matter entrusted
to the discretion of the trial court, whose order is reviewed
de novo on the record, and which will be affirmed absent an
abuse of discretion. Garza v. Garza, 288 Neb. 213, 846 N.W.2d
626 (2014).
   [5] The construction of a contract is a matter of law, in
connection with which an appellate court has an obligation to
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reach an independent, correct conclusion irrespective of the
determinations made by the court below. Strategic Staff Mgmt.
v. Roseland, 260 Neb. 682, 619 N.W.2d 230 (2000).
   [6-8] 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. State v. Merchant, 285 Neb. 456, 827 N.W.2d 473
(2013). Where the Nebraska Evidence Rules commit the evi-
dentiary question at issue to the discretion of the trial court,
an appellate court reviews the admissibility of evidence for an
abuse of discretion. Id. An abuse of discretion occurs when a
trial court’s decision is based upon reasons that are untenable
or unreasonable or if its action is clearly against justice or con-
science, reason, and evidence. Id.

                          V. ANALYSIS
                      1. Equitable Estoppel
   In the first argument section of his brief, Furstenfeld asserts
the district court should have applied the principles of equita-
ble estoppel to overrule Pepin’s motion to enforce. He reasons
that Pepin effectively withdrew her motion to enforce the May
16, 2012, agreement when she continued to litigate her modi-
fication action after filing the motion to enforce. Furstenfeld
highlights the fact that Pepin filed numerous motions after
her motion to enforce which included an amended motion to
take Furstenfeld’s deposition, a motion to release Furstenfeld’s
medical records, a motion regarding parenting time during
Christmas 2013, and a motion to suspend Furstenfeld’s parent-
ing time. Pepin argues that we should not address this argu-
ment because Furstenfeld did not raise the issue of equitable
estoppel before the district court.
   [9,10] Furstenfeld has not properly preserved this issue
for appeal. First, we observe that he does not assign error to
this issue in his brief. For an appellate court to consider an
alleged error, a party must specifically assign and argue it.
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Melanie M. v. Winterer, 290 Neb. 764, 862 N.W.2d 76 (2015).
Even if we generously assume that this argument somehow
relates to one of the four errors Furstenfeld has assigned, this
issue was not presented to the district court at the hearing
on the motion to enforce. At the hearing, Furstenfeld argued
against Pepin’s motion to enforce on the ground that Catlett
did not have authority to enter into the settlement agreement.
Nothing remotely resembling the doctrine of equitable estop-
pel was raised as an issue at the hearing. As has long been the
case, appellate courts do not generally consider arguments and
theories raised for the first time on appeal. State v. Ortega, 290
Neb. 172, 859 N.W.2d 305 (2015); Bedore v. Ranch Oil Co.,
282 Neb. 553, 805 N.W.2d 68 (2011); Tolbert v. Jamison, 281
Neb. 206, 794 N.W.2d 877 (2011).

                   2. Evidence at Hearing on
                       Motion to Enforce
   In his first assigned error, Furstenfeld attacks the district
court’s evidentiary rulings regarding three separate exhib-
its. He argues the court should not have received into evi-
dence an e-mail message sent May 15, 2012, from Catlett
to Poppe, the proposed stipulation, or a January 2014 letter
from Poppe addressed to Catlett. We separately analyze each
exhibit below.

                   (a) May 15, 2012, E-mail
   At the hearing, Pepin sought to introduce a copy of an
e-mail Poppe received from Catlett. This e-mail indicated
Furstenfeld’s willingness to settle the case and included six
settlement terms. Furstenfeld objected to the court’s receipt
of this exhibit on relevance and hearsay grounds. The dis-
trict court overruled Furstenfeld’s objections and stated
that it would receive only the portions of the exhibit which
were admissible and only for a limited purpose. On appeal,
Furstenfeld maintains his contention that this e-mail was irrel-
evant and hearsay.
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   [11-14] Under Neb. Evid. R. 402, Neb. Rev. Stat. § 27-402
(Reissue 2008), all relevant evidence is admissible unless there
is some specific constitutional or statutory reason to exclude
such evidence. State v. Stricklin, 290 Neb. 542, 861 N.W.2d
367 (2015). Evidence which is not relevant is not admissible.
Id. 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 probable or less probable
than it would be without the evidence. Id. A trial court has the
discretion to determine the relevancy and admissibility of evi-
dence, and such determinations will not be disturbed on appeal
unless they constitute an abuse of that discretion. Sturzenegger
v. Father Flanagan’s Boys’ Home, 276 Neb. 327, 754 N.W.2d
406 (2008).
   [15] We find this exhibit to be relevant to the determination
of this action. Pepin asserted that she and Furstenfeld reached
a settlement agreement; Furstenfeld denied that an agreement
had been reached and also argued that Catlett never had author-
ity to enter into a settlement agreement or engage in settlement
negotiations. Clearly, this exhibit has some probative value
relating to the issue of whether Catlett had authority to enter
into a settlement agreement or engage in settlement negotia-
tions. For evidence to be relevant, all that must be established
is a rational, probative connection, however slight, between the
offered evidence and a fact of consequence. Griffith v. Drew’s
LLC, 290 Neb. 508, 860 N.W.2d 749 (2015). The district court
did not abuse its discretion when it determined this exhibit
was relevant.
   Furstenfeld also claims this e-mail is hearsay because Catlett
did not have authority to act as his agent and make state-
ments on his behalf. Neb. Evid. R. 801(4)(b), Neb. Rev. Stat.
§ 27-801(4)(b) (Reissue 2008), provides in relevant part that a
statement is not hearsay if
      [t]he statement is offered against a party and is (i) his
      own statement, in either his individual or a representative
      capacity, . . . (iii) a statement by a person authorized by
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      him to make a statement concerning the subject, or (iv) a
      statement by his agent or servant within the scope of his
      agency or employment . . . .
There is no dispute that Pepin was offering the statements in
the e-mail against Furstenfeld.
   [16] Since this e-mail was offered against Furstenfeld, the
next question is whether the statements made within the e-mail
were made by Catlett while he was acting within the scope of
his agency or employment. We note that Catlett states within
the e-mail that Furstenfeld authorized him to make the offer.
However, in his brief, Furstenfeld argues that this statement
should have no bearing on the issue of whether Catlett actually
had authority to make statements on his behalf. On the issue of
an attorney’s authority to make statements on behalf of a client,
the Nebraska Supreme Court has held that when an attorney
appears in a cause, there is a presumption that the attorney
has authority and that presumption continues until the want of
such authority is established. See, Lennon v. Kearney, 132 Neb.
180, 271 N.W. 351 (1937); Nichols Media Consultants v. Ken
Morehead Inv. Co., 1 Neb. App. 220, 491 N.W.2d 368 (1992).
The burden of proof of such want of authority is upon the party
asserting the same. Id.
   We find no merit to Furstenfeld’s arguments that his tes-
timony that Catlett was not authorized to make any state-
ments on his behalf was sufficient to rebut the presumption
of such authority. The court’s order demonstrates that it deter-
mined Furstenfeld’s testimony on this issue was not conclusive.
Rather, the court found the evidence established that Catlett
was authorized to act on his behalf. There was no error in this
determination, and this exhibit was not hearsay.
   Furstenfeld’s arguments relating to the court’s receipt of this
exhibit in evidence are without merit.

                  (b) Proposed Stipulation
  Furstenfeld also asserts that the district court should not
have received the proposed stipulation into evidence because
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it was not relevant. He focuses on the fact that Pepin’s motion
stated that the parties had reached a settlement agreement
on May 21, 2012, whereas she testified at the hearing that
the agreement was reached on May 16. Therefore, he argues
the proposed stipulation was irrelevant because it did not
tend to prove or disprove the fact that the parties reached an
agreement on May 21. In response, Pepin states that this dis-
crepancy in date was clearly recognized by the parties at the
hearing and that Furstenfeld did not raise this discrepancy as
an issue.
   Furstenfeld’s arguments are not persuasive. It is quite clear
from the record that Pepin sought to enforce the settlement
agreement she believed the parties reached on May 16, 2012.
The date discrepancy was not raised at the hearing, and there
is nothing in the record which demonstrates that this discrep-
ancy was material to the outcome of the case. The proposed
stipulation exhibit was clearly relevant to the issue of whether
the parties had reached an oral settlement agreement prior
to trial.

                   (c) January 16, 2014, Letter
   Furstenfeld’s final evidentiary challenge relates to the court’s
receipt of the January 16, 2014, letter Poppe sent to Catlett. In
this letter, Poppe stated that he intended to call Catlett as a
witness at the hearing on the motion to enforce if Furstenfeld
continued to refuse to execute the proposed stipulation. Poppe
offered this letter as evidence at the hearing and informed
the court that he was offering this letter to reflect that he had
attempted to avoid calling Catlett as a witness, but had no other
choice. Other than Poppe’s statements to the court, Pepin did
not provide any other foundation for this exhibit.
   [17] For the sake of argument, we will assume that
Furstenfeld correctly argues that the court’s receipt of this
exhibit constituted error on the basis of relevance. However,
to constitute reversible error in a civil case, the admission or
exclusion of evidence must unfairly prejudice a substantial
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right of a litigant complaining about evidence admitted or
excluded. Martensen v. Rejda Bros., 283 Neb. 279, 808 N.W.2d
855 (2012). Furstenfeld cannot show the admission of this
letter into evidence prejudiced a substantial right because the
district court did not rely upon this exhibit in ruling upon
Pepin’s motion. In fact, this exhibit is not even mentioned in
the court’s order. This assigned error is without merit.

                   3. Pepin’s Calling Catlett
                            as Witness
   Furstenfeld also assigns error to the district court’s deci-
sion to permit Pepin to call Catlett as a witness at the hearing.
He asserts that it was not necessary for Pepin to call Catlett
as a witness to prove that an oral agreement was reached.
According to Furstenfeld, the court’s decision to allow Catlett’s
testimony and then subsequently rely on that testimony to sus-
tain Pepin’s motion “rigged” the game in Pepin’s favor. Brief
for appellant at 23.
   [18-20] When a party seeks to disqualify an opposing attor-
ney by calling that attorney as a witness, the court must strike
a balance between the potential for abuse and those instances
where the attorney’s testimony may be truly necessary to the
opposing party’s case. See Beller v. Crow, 274 Neb. 603, 742
N.W.2d 230 (2007). The party moving to disqualify an oppos-
ing attorney bears the burden of establishing that the attorney’s
testimony will be necessary. Id. A party seeking to call oppos-
ing counsel can prove that counsel is a necessary witness by
showing that (1) the proposed testimony is material and rel-
evant to the determination of the issues being litigated and (2)
the evidence is unobtainable elsewhere. Id.
   The record from the hearing on the motion to enforce
reveals that the district court allowed Pepin to question Catlett
on a “very limited” basis. Specifically, Pepin sought to estab-
lish foundation for the e-mail Catlett sent to Poppe regarding
the parties’ agreement and to establish that Furstenfeld engaged
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                       Cite as 23 Neb. App. 155

in telephone communication with Catlett on May 16, 2012,
during the settlement negotiations.
   We find no error in the district court’s determination to
allow Pepin to question Catlett on a limited basis. Catlett’s
testimony was material to the issues being litigated. Pepin
demonstrated to the court that Catlett’s testimony would con-
firm the authenticity of the e-mail sent to Poppe regarding the
proposed stipulation and would also establish that Furstenfeld
participated in settlement negotiations through telephone com-
munication. The record reveals there was no other witness who
could provide this evidence. Because Pepin established that
Catlett’s testimony was material and relevant to the litigated
issues and could not be obtained elsewhere, the district court
correctly permitted the questioning.
   Furstenfeld also argues that Neb. Rev. Stat. § 7-107 (Reissue
2012) prohibited Catlett from testifying to establish the exis-
tence or terms of the agreement. The relevant portion of
§ 7-107 provides:
         An attorney or counsel has power: . . . (2) to bind
      his client by his agreement in respect to any proceeding
      within the scope of his proper duties and powers; but no
      evidence of any such agreement is receivable except the
      statement of the attorney himself, his written agreement
      signed and filed with the clerk, or an entry thereof upon
      the records of the court . . . .
Furstenfeld contends that the language “statement of the attor-
ney himself” should only apply to statements made in open
court that there is an agreement to settle and recitations of the
agreement’s terms. In other words, he concludes an attorney’s
testimony is not permitted under the statute. He asserts that
Catlett never made such a statement during the hearing.
   In support of his arguments, Furstenfeld relies upon two
cases, Heese Produce Co. v. Lueders, 233 Neb. 12, 443
N.W.2d 278 (1989), and Luethke v. Suhr, 264 Neb. 505, 650
N.W.2d 220 (2002). We have closely reviewed these cases
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                      FURSTENFELD v. PEPIN
                       Cite as 23 Neb. App. 155

and determine that neither case squarely addresses the issue
of whether an attorney’s testimony as a witness satisfies the
statutory language cited above. Heese Produce Co. discusses,
among other issues, the failure to object to written corre-
spondence adduced to prove the existence of a settlement
agreement. Luethke primarily discusses when, and under what
circumstances, a lawyer may bind his or her client to a settle-
ment agreement entered into without express authority from
the client.
   Upon our review, we agree with the district court’s conclu-
sion that a settlement agreement may be established by the
testimony of the attorney of the party sought to be bound. The
plain language of § 7-107 supports such a result. See Fisher v.
PayFlex Systems USA, 285 Neb. 808, 829 N.W.2d 703 (2013)
(absent statutory indication to contrary, appellate court gives
words in statute their ordinary meaning). We further note that
attorney testimony was received in Luethke v. Suhr, supra, in
an attempt to establish the existence of a settlement agreement.
This assigned error is without merit.

                  4. Sufficiency of Evidence on
                        Motion to Enforce
   In addition to the previous errors discussed above,
Furstenfeld also argues there was not sufficient evidence for
the district court to sustain Pepin’s motion to enforce the agree-
ment. He focuses his discussion on the fact that Pepin could
not produce any direct evidence to establish that Furstenfeld
had given Catlett express authority to enter into the settlement
agreement. We reject this argument.
   [21,22] Nebraska case law establishes that a settlement
agreement is subject to the general principles of contract law.
See Woodmen of the World Life Ins. Soc. v. Kight, 246 Neb.
619, 522 N.W.2d 155 (1994). To have a settlement agreement,
there must be a definite offer and an unconditional acceptance.
Heese Produce Co. v. Lueders, supra.
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                       FURSTENFELD v. PEPIN
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   [23-25] Nebraska law is clear that the decision to settle a
lawsuit belongs to the client; because the client bears the risk
when settling or refusing to settle a dispute, it is the client, not
the lawyer, who should assess whether the risk is acceptable.
See Luethke v. Suhr, supra. Although lawyers retain apparent
authority to make procedural and tactical decisions through the
existence of the attorney-client relationship, a lawyer cannot
settle a client’s claim without express authority from the cli-
ent. Id. Disputes over a lawyer’s authority to settle are factual
issues to be resolved by the trial court, and an appellate court
will not set aside a trial court’s factual findings regarding
settlement disputes unless such findings are clearly erroneous.
See id.
   In this case, the district court’s order reviewed the evidence
adduced at the hearing and found that Catlett had author-
ity to settle the case on Furstenfeld’s behalf. The evidence
at the hearing established that Furstenfeld and Catlett were
in telephone communication during the negotiations on May
16, 2012. After these negotiations, Catlett and Poppe jointly
informed the court, without any qualifications, that the matter
had been settled. Thereafter, Catlett sent an e-mail response to
Poppe’s proposed stipulation in which he stated the proposed
stipulation accurately reflected the parties’ agreement. Catlett
further testified at the hearing that he did not have any reason
to believe the proposed stipulation was not the same document
he reviewed 2 years prior to the hearing.
   The court also specified in its order that it did not find
Furstenfeld’s testimony determinative on the issue of whether
Catlett had been given authority to settle. In effect, this finding
was a determination that Furstenfeld’s testimony was not as
credible as Pepin’s evidence.
   Having reviewed the record, we conclude the district court
did not clearly err in determining that Furstenfeld granted
Catlett the necessary authority to settle the modification action.
The record contains sufficient evidence for the district court to
have sustained Pepin’s motion to enforce.
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                      FURSTENFELD v. PEPIN
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                         5. Child Support
   For his final assignment of error, Furstenfeld claims the
district court erred when it adopted Poppe’s child support cal-
culations in its August 29, 2014, order. He broadly asserts that
there is no legal significance to any agreement that purports to
establish or modify a child support obligation.
   [26-28] In general, child support payments should be set
according to the Nebraska Child Support Guidelines. Anderson
v. Anderson, 290 Neb. 530, 861 N.W.2d 113 (2015). Stipulated
agreements of child support are required to be reviewed against
the guidelines. Molina v. Salgado-Bustamante, 21 Neb. App.
75, 837 N.W.2d 553 (2013). If the court approves a stipulation
which deviates from the guidelines, specific findings giving
the reason for the deviation must be made. Id.
   The child support worksheet attached to the August 29,
2014, order shows gross monthly income for Pepin of $1,250
and for Furstenfeld of $35,000; with respective net incomes of
$1,101.08 and $22,740.09, for a total of $23,841.17 combined
net monthly income. The total obligation of child support
for the parties combined net monthly income is $2,201; with
the father’s share at $2,099. In addition, a “Section 4-203(C)
Additional Support Worksheet (Optional)” is attached which
sets forth the net monthly combined income above $15,000
at $8,841.17. This worksheet then sets the additional support
pursuant to Neb. Ct. R. § 4-203(C) (rev. 2011) at $884.12,
resulting in Furstenfeld’s final share of $2,943.
   Section 4-203(C) of the child support guidelines provides
in part:
      [I]f total net income exceeds $15,000 monthly, child sup-
      port for amounts in excess of $15,000 monthly may be
      more but shall not be less than the amount which would
      be computed using the $15,000 monthly income unless
      other permissible deviations exist. To assist the court and
      not as a rebuttable presumption, the court may use the
      amount at $15,000 plus: 10 percent of net income above
      $15,000 for one, two, and three children; 12 percent of
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                      FURSTENFELD v. PEPIN
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     net income above $15,000 for four children; 13 percent
     of net income for five children; and 14 percent of net
     income for six children.
   The worksheet adopted by the court complied with the pro-
visions of § 4-203(C) as the additional support was 10 percent
of Furstenfeld’s net income above $15,000. While there is no
evidence in the record regarding the parties’ incomes at the
time of the amended decree or the hearing on the motion to
enforce, the parties agreed in the stipulation that Furstenfeld’s
child support obligation would be increased to $3,000 and that
a child support calculation worksheet would be attached. The
child support calculation worksheets attached to the court’s
order are consistent with the guidelines, and we can find no
abuse of discretion in the court’s adoption of the stipulation
and the child support worksheets.

                      VI. CONCLUSION
   The district court did not err when it concluded that Pepin
and Furstenfeld had reached a settlement agreement. We affirm
the court’s order.
                                                   A ffirmed.
