My ex has decided to give up his paternal rights to our 2 yr old son, and wants to get it done as soon as possible, my fiancé wants to adopt him when we get married but since he's in the Navy on deployment it may be a while before this happens, I want to know if, once my ex does sign over his rights, is there any way he can try to get them back? And if there is, is there any way to try to prevent that from happening?