[ 1 Our question involves the enforceability of a divorcee decree by which the parties purport to agree "to leave the child support open after the minor child reaches the age of eighteen and/or complete high school ..." *924based on the needs of the child, if any. The parties agree that the child is a “special needs” child with some degree of retardation and seizure problems.
¶2 Mother and Father divorced in 1993 when their child was fifteen years old. Father stopped providing medical insurance in 2000. Mother then sought an order from the District Court to (1) compel Father to provide medical insurance, (2) pay additional child support, (3) reimburse Mother for payments made to maintain the insurance and for medical expenses, (4) pay child support payments that were unpaid since 1999, and (5) adjudicate future support amounts needed by the child. She alleged that at the time of the divorce the parties agreed that Father would provide support after the child was 21 years old.
¶ 3 Father responded to Mother’s application with a motion to dismiss. He stated that he stopped making the child support payments in May of 1999 after the child graduated from high school at the age of 21 years. He argued that the District Court was without jurisdiction to order payments to support a child after the child has reached the age of 21 years.
¶4 The trial court heard argument of counsel and granted the motion to dismiss. Mother appealed and the judgment was affirmed by the Court of Civil Appeals. We vacate the opinion of the Court of Civil Appeals and reverse the judgment of the District Court.
¶ 5 The Father maintains that the decree is not a judgment by consent, or “consent decree.” We have discussed the characteristics of a consent decree:
A consent judgment is the agreement of the parties entered upon the record with the sanction of the court. McRary v. McRary, 228 N.C. 714, 719, 47 S.E.2d 27, 31 (1948). A consent decree in a divorce is the result of negotiations between the parties and subsequent settlement of the issues involved, which settlement is then presented to the court as a proposed judgment. Although it is not a judicial determination of the rights of the parties, it acquires the status of a judgment through the approval of the judge of the pre-exist-ing agreement of the parties.
Whitehead v. Whitehead, 1999 OK 91, ¶ 9, 995 P.2d 1098, 1101, (note omitted and emphasis added).
Father’s brief describes the events leading up to the decree: “After the parties had been litigating the trial for a matter of days, settlement discussions ensued between the parties and their respective counsel that led to the Journal Entry Order and Decree of Divorce .... ” The record supports this description in that the decree states that the parties agreed to the provisions of the divorce decree “with regard to all issues.” Decree of Divorce, O.R. at 9. The decree is a judgment by consent or a “consent decree.”
¶ 6 Of course, characterizing the decree as a consent decree does not determine that the parties agreed to a particular matter. The controversy in the trial court centered on one provision of the 1993 divorce decree. It states that:
IT IS THEREFORE ORDERED, ADJUDGED AND DECREED by the Court that the Defendant shall pay child support in the amount of Four Hundred Dollars ($400.00) per month, deviated from the child support guidelines, attached hereto as Exhibit “A”, as agreed upon by the parties. Due to the special needs of the minor child, the parties have agreed to leave the child support open after the minor child reaches the age of eighteen (18) and/or completes high school, and the Court will retain jurisdiction for either party to file an application for further support based upon the specific needs and requirements of the minor child, if any.
Id. O.R. at 11.
Mother claims that the trial court has jurisdiction to order more child support because of Father’s agreement. Father claims that a District Court has no subject matter jurisdiction to compel child support payments for the support of children after they have reached the age of 21 years, and that subject matter jurisdiction cannot be created by an agreement of parties.
¶ 7 We have said that a parent has a legal duty to support his or her child until *925the child reaches the age of majority. State, ex rel. Dept. of Human Services ex rel. Jones v. Baggett, 1999 OK 68, ¶ 22, 990 P.2d 235, 244; Abrego v. Abrego, 1991 OK 48, 812 P.2d 806, 811. The divorce decree in this case was pronounced on June 17, 1998, and the relevant statute in effect at that time stated that:
Any child shall be entitled to support by the parents until the child reaches eighteen (18) years of age. If a dependent child is regularly and continuously attending high school, said child shall be entitled to support by the parents through the age of eighteen (18) years.
43 O.S$.Supp.1998 § 112(D), (eff, June 7, 1993).
Thus, at the time of the decree this statute-based obligation for child support did not extend beyond the child's nineteenth birthday. Id.
18 But the decree in this case is a consent decree, and parties to a consent decree may agree to obligations between themselves that exceed those required by law.
If the agreement between the parties regarding support and maintenance is intended as final and binding, leaving nothing for determination by the court on the question of the amount of the allowance, such decree is not subject to modification without the consent of both parties. Stuart, 1976 OK 107, T 14, 555 P.2d at 615. Such an agreement between the parties is enforceable and valid even though it does what a trial court cannot do, provided the agreement does not contravene public policy.
Whitehead v. Whitehead, 1999 OK 91, 110, 995 P.2d 1098, 1101, (emphasis added). Thus, when a trial court is requested to enforce a child-support obligation upon a parent an important issue must be addressed: What is the source of that obligation? Does the obligation spring from mandatory law or does it spring from a consensual agreement? We noted this distinction in G@reeson v. (Gree-son, 1958 OK 111, 257 P.2d 276.
T9 In Greeson we observed that a trial court did not possess statutory power to modify child support retroactively, but the
parties could agree to such modification and incorporate such agreement in a judgment by consent. We explained that such a consent decree was judicially enforceable.
With this contention we agree. Under 12 ©.8.1941 § 1277 the court has authority to modify an order for child support prospectively. The court does not have authority to make the modifying order operate retroactively. Sango v. Sango, 121 Ok. 288, 249 P. 925; Reynolds v. Reynolds, 192 Okl. 564, 187 P.2d 914. Therefore, if the order of December 21, 1946 had been entered by the court upon the merits after a trial of the issues it would have been void insofar as it had the effect of relieving the defendant of liability for unpaid installments accrued up to the time of the entry of the order.
However, it is agreed that the order of December 21, 1946 was a consent order entered by the court upon the agreement and consent of the parties. While in its retroactive aspect it is void as a court order, yet being a consent order, it is in the nature of a contract, and in the absence of fraud or mistake, is a binding obligation between the parties thereto.
Greeson v. Greeson, 257 P.2d at 278. (emphasis added)
Just as parties may consent to a retroactive adjustment of their personal rights, they may also contract as to their personal rights in the future. For example, in Kittredge v. Kittredge, 1995 OK 30, 911 P.2d 908, we explained that a consent decree awarding the wife a percentage of the husband's future income in Hieu of property division was enforceable, even though the statute would otherwise have prohibited an order to that effect:
The husband argues the trial court did not have the jurisdictional power to divide his future earnings because the consent of his rights even though he consented to the division. In Eitinger v. Ettinger, 687 P .2d 63, 65 (Okla 1981), this Court held that under section 1278 of title 12 of the Oklahoma Statutes (now Okla.Stat.tit. 43 § 121), a district court did not have jurisdiction to divide a husband's future earning absent a recitation in the decree the *926parties intended to cireamvent the statute. The Court, however, recognized that where the parties had entered into a consent agreement which sought to avoid the strictures of the statute, the district court would have jurisdiction to enter such an order. Further, an express waiver of statutory rights in the consent decree was not required, only an agreement "which seeks to avoid the strictures of Section 1278."
Kittredge v. Kittredge, 911 P2d at 904. Thus, the parties may, as a general proposition, agree between themselves as to future child support payments.
Father further argues that a "consent decree may not leave anything for determination by the trial court." He relies upon language in Whitehead stating that: "If the agreement between the parties regarding support and maintenance is intended as final and binding, leaving nothing for determination by the court on the question of the amount of the allowance, such decree is not subject to modification without the consent of both parties." Whitehead v. Whitehead, 1999 OK 91, at 110, 995 P.2d at 1101, emphasis added. This language addresses the finality of an obligation, and not whether the amount of an obligation may be contractually set for a future determination. We have allowed consent decrees to possess obligations where the amount thereof is determined at a future date. Kittredge v. Kittredge, supra.
111 Once we recognize that parties may agree to alter their obligations the next steps are determining if such agreement did occur and the substance of the agreement. We use principles of contract law to make these determinations. We have said that we construe a consent judgment "as other contracts" and ascertain the intent of the parties.
An agreed judgment is in the nature of a contract and is to be construed as other contracts. Grayson v. Pure Oil Co., 189 Okl. 550, 118 P.2d 644; Insurance Service Co. v. Finegan, 196 Okl. 441, 165 P.2d 620. The intention of the parties is to be ascertained from the writing alone, if possible. 15 0.98.1941 § 155.
(Greeson v. Greeson, 257 P .2d at 278-279.
112 Father points to the lack of specificity in an amount to be determined in the future. A lack of specificity in either the amount or scope of an obligation does not necessarily mean an absence of a judicially enforceable obligation. We have explained that even if a provision of a contract is too vague and indefinite to determine the intent of the parties, their conduct may supply the necessary information to determine intent of the parties. Bartlett v. Sterling Const. Co., 1972 OK 67, 499 P.2d 425, 429.
118 The intent of the parties at the time they entered into an agreement controls the meaning of their written contract, and the statutory rules for ascertaining intent are set out at 15 0.8.2001 §§ 151 through 157. Founders Bank and Trust Co. v. Upsher, 1992 OK 35, 830 P.2d 1855, 1361.1 The trial court made its decision in the context of a motion to dismiss challenging the jurisdiction of the trial court to award statutorily mandated support after a child has reached her majority. The trial court did not make findings of fact or law on the issue *927of the parties' intent, the essential elements of an agreement, or the contested portion of the divorce decree. Further, although Mother alleges that a judicially enforceable agreement exists, neither Father or Mother identify the relevant principles of contract law that may apply to the controversy in support of their respective positions. This Court will not exercise its appellate jurisdiction to make first instance determinations on disputed questions of fact or law. Oklahoma Public Employees Association v. Oklahoma Dept. of Central Services, 2002 OK 71, 121, 55 P.3d 1072, 1081; Patel v. OMH Medical Center, Inc., 1999 OK 83, 1 42, 987 P.2d 1185, 1201. This cause must, therefore, be remanded to the trial court for further proceedings.
114 We note that while this matter was pending the Legislature added 48 0.9.2001 § 112.14, and it provides that a court may order for the support of a child of any age in the event of certain disabilities.2 Because we reverse the judgment of the trial court and remand the matter to that court we need not request briefs from the parties or address the applicability of new § 112.14, if any, to this controversy.
115 The trial court dismissed the claims with two conclusions: first, that it did not possess subject matter jurisdiction, and secondly, that onee a child reaches his or her majority the child is the proper party to bring a legal action against a parent for the parent's failure to pay support during that child's minority. A child does possess an independent right to maintain an action and to request support and maintenance. State
*928Dept. of Human Services ex rel. K.A.G. v. T.D.G., 1998 OK 126, 861 P.2d 990, 993. Whether the disputed portion of the decree is in fact an agreement allowing Mother to act on the child's behalf, and the effect of such an agreement upon Father's right to challenge Mother's representative status, if any, was not addressed by the trial court. The trial court's order must be reversed on this point as well.
116 Generally, we use a de novo standard to review a trial court's dismissal of a party's petition for relief because such dismissal is usually based solely upon an issue of law and not fact. Miller v. Miller, 1998 OK 24, 115, 956 P.2d 887, 894. Father's motion to dismiss argued that no consent decree existed, and that the parties could not, as a matter of law, agree to subject matter jurisdiction. The trial court order determines that no subject matter jurisdiction existed.
117 That order is correct insofar as it determines a lack of jurisdiction to award statutory child support under Title 43. But district courts have jurisdiction to adjudicate the existence and effect of contracts. Here the Mother's claim is for enforcement of a contract she alleges to be in effect. She alleges consideration for the bargain by way of her agreeing to give up part of her statutorily calculated child support. The Father does not dispute this, but the trial court has never adjudicated the existence or non-existence of that alleged contract. The trial court did not determine whether Father agreed to pay child support after the child reached her majority. We will not determine in the first instance whether the decree contains such an agreement. Oklahoma Public Employees Association v. Oklahoma Dept. of Central Services, supra; Patel v. OMH Medical Center, Inc., supra. The Mother is entitled to her day in court to prove what, if anything, the parties agreed to, and whether the Father is in fact in breach of any agreement.
T18 The opinion of the Court of Civil Appeals is vacated." The judgment of the District Court is reversed, and the matter is remanded to the District Court for further proceedings consistent with this opinion.
1 19 WATT, C.J., OPALA, V.C.J., HODGES, HARGRAVE, KAUGER, SUMMERS, JJ., concur. { 20 LAVENDER, BOUDREAU, WINCHESTER, JJ., dissent.. 15 0.$.2001 § 151: "All contracts, whether public or private, are to be interpreted by the same rules, except as otherwise provided by law."
15 0.$.2001 § 152; "A contract must be so interpreted as to give effect to the mutual intention of the parties, as it existed at the time of contracting, so far as the same is ascertainable and lawful."
15 0.8.2001 § 153: "For the purpose of ascertaining the intention of the parties to a contract, if otherwise doubtful, the rules given in this chapter are to be applied."
15 0.$.2001 § 154: "The language of a contract is to govern its interpretation, if the language is clear and explicit, and does not involve an absurdity."
15 0.$.2001 § 155: "When a contract is reduced to writing, the intention of the parties is to be ascertained from the writing alone, if possible, subject, however, to the other provisions of this article."
15 § 156: "When through fraud, mistake, or accident a written contract fails to express the real intention of the parties, such intention is to be regarded, and the erroneous part of the writing disregarded."
15 0.$.2001 § 157: ''The whole of a contract is to be taken together, so as to give effect to every part, if reasonably practicable, each clause helping to interpret the others."
. 43 0.98.2001 § 112.14 (eff. July 1, 2001).
§ 112.14. Definitions-Child support-Parental rights and duties-Actions and jurisdiction
A. In this section:
1. "Adult child" means a child eighteen (18) years of age or older.
2. "Child" means a son or daughter of any age.
B. 1. The court may order either or both parents to provide for the support of a child for an indefinite period and may determine the rights and duties of the parents if the court finds that:
a. the child, whether institutionalized or not, requires substantial care and personal supervision because of a mental or physical disability and will not be capable of self-support, and
b. the disability exists, or the cause of the disability is known to exist, on or before the eighteenth birthday of the child.
2. A court that orders support under this section shall designate a parent of the child or another person having physical custody or guardianship of the child under a court order to receive the support for the child. The court may designate a child who is eighteen (18) years of age or older to receive the support directly.
C. 1, A suit provided by this section may be filed only by:
a. a parent of the child or another person having physical custody or guardianship of the child under a court order, or
b. the child if the child:
(1) is eighteen (18) years of age or older,
(2) does not have a mental disability, and
(3) is determined by the court to be capable of managing the child's financial affairs.
2. The parent, the child, if the child is eighteen (18) years of age or older, or other person may not transfer or assign the cause of action to any person, including a governmental or private entity or agency, except for an assignment made to the Title IV-D agency.
D. 1. A suit under this section may be filed:
a. regardless of the age of the child, and
b. as an independent cause of action or joined with any other claim or remedy provided by this title. |
2. If no court has continuing, exclusive jurisdiction of the child, an action under this section may be filed as an original suit.
3. If there is a court of continuing, exclusive jurisdiction, an action under this section may be filed as a suit for modification pursuant to Section 115 of this title.
E. In determining the amount of support to be paid after a child's eighteenth birthday, the specific terms and conditions of that support, and the rights and duties of both parents with respect to the support of the child, the court shall determine and give special consideration to:
1. Any existing or future needs of the adult child directly related to the adult child's mental or physical disability and the substantial care and personal supervision directly required by or related to that disability;
2. Whether the parent pays for or will pay for the care or supervision of the adult child or provides or will provide substantial care or personal supervision of the adult child;
3. The financial resources available to both parents for the support, care, and supervision of the adult child; and
4. Any other financial resources or other resources or programs available for the support, care, and supervision of the adult child.
F. An order provided by this section may contain provisions governing the rights and duties of both parents with respect to the support of the child and may be modified or enforced in the same manner as any other order provided by this title.