Rhonda S. Wittland, now known as Rhonda S. Johnson,appeals the trial court's January 31, 2005, order dismissing herpetition to set child support. She alleges that the court'sorder made child support nonmodifiable in violation of section502(f) of the Illinois Marriage and Dissolution of Marriage Act(Dissolution Act) (750 ILCS 5/502(f) (West 2004)). We reverseand remand.

I. BACKGROUND

Rhonda and Roger D. Wittland married on September 5,1987. The couple had two children during the marriage, Jacob,born June 23, 1988, and Alexis, born July 25, 1995. On June 2,1998, Roger filed a petition for dissolution of marriage. Thetrial court entered a judgment of dissolution on August 12, 1998. The parties had joint legal custody of the children, but Rogerhad physical custody. Because she was unemployed at the time,the court ordered Rhonda to pay $10 per month in child support. On August 22, 2000, the trial court increased the amount of childsupport to $276 per month as Rhonda had since obtained a job.

On April 12, 2004, Rhonda and Roger entered into anagreement modifying the dissolution judgment wherein Rhondareceived custody of Jacob, and Roger retained custody of Alexis. Paragraph 5 of the agreed order stated that "due to each partyhaving physical custody of one child, no child support is orderedherein and [Rhonda's] obligation is hereby terminated effectiveApril 1, 2004."

On September 15, 2004, Rhonda filed a petition tomodify the April 2004 agreed order. She alleged a substantialchange in circumstances in that Jacob had turned 16, was driving,and, therefore, had increased expenses, including car insuranceand a vehicle loan. Roger filed a motion to dismiss, which thetrial court granted on December 3, 2004. The court found that itcould not modify a nonexistent order for child support; theparties had agreed that neither would pay child support.

On December 14, 2004, Rhonda filed a petition to setchild support, citing section 505 of the Dissolution Act, which requires a noncustodial parent to pay 20% of his or her netincome as child support for one child. Roger again filed amotion to dismiss Rhonda's petition, which the trial courtgranted on December 31, 2004. Citing In re Marriage of Steadman,283 Ill. App. 3d 703, 708-09, 670 N.E.2d 1146, 1150-51 (1996), itfound that the statutory guidelines for child support may bedisregarded in cases involving split custody and no specificguidelines exist where the parties have such an agreement. Thecourt also stated that where the parties agree that neither partyis obligated to pay child support because of split custody, acourt does not abuse its discretion in not further addressing theissue of child support, citing In re Marriage of Deem, 328 Ill.App. 3d 453, 458, 766 N.E.2d 661, 665-66 (2002). This appealfollowed.

II. ANALYSIS

Rhonda urges that the court's dismissal of her petitions to set or modify child support without hearing evidence onthe matter resulted in a de facto nonmodifiable support order inviolation of section 502(f) of the Dissolution Act (750 ILCS5/502(f) (West 2004)). We review de novo a trial court's grantof a motion to dismiss. Friends of the Parks v. Chicago ParkDistrict, 203 Ill. 2d 312, 319-20, 786 N.E.2d 161, 165 (2003).

When it dismissed Rhonda's petition to set childsupport, the trial court cited Steadman, 283 Ill. App. 3d at 708,670 N.E.2d at 1150, for the propositions that a court may "disregard the statutory guidelines" where the parties have agreed tosplit custody and that "there are no specific guidelines tofollow" in such cases. However, Steadman also stated that acourt may "consider the factors listed in section 505 of the[Dissolution] Act." Steadman, 283 Ill. App. 3d at 708, 670N.E.2d at 1150. In re Marriage of White, 204 Ill. App. 3d 579,582, 561 N.E.2d 1387, 1389 (1990), upon which Steadman relied,held that though "[t]here are no guidelines for trial courts whencustody is split between the parties," "[t]he factors set forthin section 505 do apply and should be considered." NeitherSteadman nor White supports the conclusion that a trial court mayaltogether refuse to consider whether child support is appropriate in a split-custody case.

Further, courts have a responsibility to protect thebest interests of the children in child-support matters. In reMarriage of Case, 351 Ill. App. 3d 907, 911, 815 N.E.2d 67, 71(2004). To this end, courts are not bound by the parties'agreements as to child support (Case, 351 Ill. App. 3d at 911,815 N.E.2d at 71), and settlement agreements may not be madenonmodifiable in that regard (Steadman, 283 Ill. App. 3d at 707-08, 670 N.E.2d at 1150). The right to modify child support is astatutory right, and parties are always able to petition thecourt upon a change in circumstances. Steadman, 283 Ill. App. 3dat 707-08, 670 N.E.2d at 1150.

In this case, section 505(a)(1) of the Dissolution Actdoes not apply to the parties' split-custody arrangement; thisdoes not, however, mandate the dismissal of Rhonda's petitions. While the trial court is not bound to order Roger to pay the 20%net income minimum for one child's support as set out in section505(a)(1) of the Dissolution Act (750 ILCS 5/505(a)(1) (West2004)), it still should consider the matter in light of thefactors listed in section 505(a)(2) (750 ILCS 5/505(a)(2) (West2004)). The parties' agreement that neither would pay childsupport does not preclude the trial court from considering theissue. By dismissing Rhonda's petitions on the grounds given,the court impermissibly prevented her from presenting evidencethat changed circumstances warranted child support for her son.III. CONCLUSION

For the reasons stated, we reverse the trial court'sjudgment and remand.

Reversed and remanded.

STEIGMANN and McCULLOUGH, JJ., concur.