I am divorced and have four children in my divorce it states that we have joint custody of all four and that I have physical custody of two and he has physical custody of two. Here is were it gets sticky all four have lived with me for two years and no child support and no help and now he has a new girlfriend and decides that he is going to keep my oldest daughter just out of the blue I want her back what do I do.

You go to court and request a change of custody and modification of support.

Right now, it seems, that he has physical custody of your daughter ordered, so it has to be changed by a court.