Use this program to ask (or "petition") the Family Court to change a support order if there is a "change in circumstances." Child Support Forms ; 4-3b.Addendum to Support Petition– Request for Child Support (IV-D) Services. Forms: Probation Forms, Presentence Investigation Forms, Child Support, Visitation, Custody and Paternity Petition Forms, Sign up for Notifications. 1. Fill out a child support modification petition. 2. File the petition with the Family Court that most recently established your order. 3. This book can help you fill out the right forms to file a Motion or opposition to a Motion. Step 1: Fill out the forms: If you have an existing case, no matter how old, use the same case title and case number. First, download and complete the request form. When the RFO form is filed, the court clerk will provide this date to you.