Section 1419.5 Of Chapter 1. Short Title And Definitions From California Probate Code >> Division 4. >> Part 1. >> Chapter 1.

. "Custodial parent" means the parent who either (a) has been awarded sole legal and physical custody of the child in another proceeding, or (b) with whom the child resides if there is currently no operative custody order. If the child resides with both parents, then they are jointly the custodial parent.