Legal Question in Family Law in Oklahoma

The statutory provision that establishes the duration for child support is found in Title 43 Okla Stat. Sec 112 which provides:

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E. Except as otherwise provided by Section 112.1A of this title, any child shall be entitled to support by the parents until the child reaches eighteen (18) years of age. If a child is regularly enrolled in and attending high school, as set forth in Section 11-103.6 of Title 70 of the Oklahoma Statutes, other means of high school education, or an alternative high school education program as a full-time student, the child shall be entitled to support by the parents until the child graduates from high school or until the age of twenty (20) years, whichever occurs first. Full-time attendance shall include regularly scheduled breaks from the school year. No hearing or further order is required to extend support pursuant to this subsection after the child reaches the age of eighteen (18) years.

In your case, since your child is still in school (and I assume is attending regularly) c/s is payable through the month of graduation (May). If you have more than one child covered by a child support order, then an Order Modifying Child Support will be necessary to terminate the obligation for c/s on the oldest child.