This is called a Petition for Custody and Support. You can start a case called a Petition for Custody and Support of Minor Children.This lets the court make custody and visitation orders and other orders. Complete the attached forms in black ink. Scan your completed forms and save as a single PDF file. This guide will take you through both of these processes, guiding you on which forms you need, how to fill them out, and how to start the filing process. A petition for custody would be filed in the juvenile, family, or domestic relations Court with jurisdiction over the child, at the county level. Find and Download official court forms for California Child Custody and Visitation. Ready to take the next step? Find and Download official court forms for California Child Custody and Visitation.