Relocation of a Pregnant Mother to Another State Prior to Birth

My question involves a child custody case from the State of: Florida
19 yr old daughter, pregnant by 20 yr old. Both living in state of Florida. Boyfriend has anger and drug problems. Verbally abusive. Daughter wants to move to another state before birth of child, due in 4 months. If she establishes residency in another state and child born in another state will it make it more difficult for father to obtain custody, shared custody? She is afraid that once child is born he will prohibit her from leaving state.

If this guy is as bad as she says, why are you not doing everything you can to get her out of there ASAP?

As of this moment, he does not have a child. They're not married, so the only way he can obtain any rights to custody/visitation is AFTER the child is born. Once the child is born, he can run to court and have a temporary order established to keep her in the state until paternity is established and custody/visitation orders are in place.

She's not his property. Get her out of there NOW.