My son wants to live with me not his mom even though she has full custody. He is with me now but doesn't want to go home what can I do?

Well that all depends on the courts decision. If there is a good reason he should stay with you then they might change the custody situation. How old is he? Some judges will let the child decide if there mature enough to make that decision. Does he want to stay with you cause he has more fun with you or is his mother doing something wrong?

You say she has full custody. Do you mean physical or Legal or both?

I'm curious about the choice of handle if you are the dad, not the mom.

Bu in any case, you have no choice. You have to send the kid back home. What you need to do, is petition the court for a change in custody. The court will then review the reasons, talk with your son and decide what's in his best interests.