This document is a sample form letter designed for individuals seeking a downward modification of their child support obligations. Addendum to Support Petition– Request for Child Support (IV-D) Services.Download a free child support modification form to propose changes to a current child support agreement. Available in PDF or Word format. Motion to Modify Child Support Forms. These forms are designed for people who agree on the terms of their child support case. Step Two: Fill out the form. If you're eligible, fill out the JFS 01849, "Request for an Administrative Review of the Child Support Order. Complete this form to request modification, termination, or reinstatement of an existing support order. A Motion to Modify Child Support (CAFC102) form is the pleading filed with the court to make changes in the best interest of your child.