Sean Penn is showing his commitment to family as he has recently petitioned the courts to legally adopt Jackson, Charlize Theron’s son. Adopted and her only child, it is reported that Jackson and Sean already have a solid relationship. In fact, Jackson has begun calling Sean, “Daddy.”

The couple has been dating for more than a year and just last November got engaged. Sources say that Penn knew if he really wanted to win Charlize’s heart, he’d have to first win Jackson’s.

Penn is the father of two adult children and has previously been married to Madonna and then to Robin Wright. The adult children, daughter Dylan and son Hopper, are from the union of Penn and Robin Wright. Still, it is rumored that Penn and Theron are anxious to expand their family. Talk of future adoptions is in the works.