VISITATION RIGHTS.

Hey guys! I need some help. So my boyfriend hasn't seen his daughter in almost a year due to the mother leaving the state we currently live in. They live in two different towns. They had a mutual agreement that he'd get his daughter om the weekends. We went to go get her and he found out that the mother and his daughter moved. He never knew where they were until I searched on FB. How should he go about getting a lawyer and getting visitation. He has paid CP since she was born and has never been behind on payments. PLEASE HELP.