How do I handle my daughter's boyfriend's mother when she controls her in my home?

How do I handle my daughter's boyfriend's mother when she controls my daughter through her son in my home? His mother thrown him out because of anger issues, etc. I felt sorry for him when he had no place to go, and rang my door bell holding one bag and a boy doll sticking out. Well, I regret it. In fact, I had told in outright to get out of my home and my daughter who was a troubled teen told me if he goes she goes. At the time it was snowing. Once my daughter ran away and another she met up with some bad people that required police istance and the local community for me to get her home. Now that she had a baby with this young man (who I don't approve of and against my wish), his mother and cousin advises him how to deal with my 18 year old daughter because I won't behave. Well, it's my house, and I have taken the stand that he must come out or I'll call the police and have him removed. Well, he convinced my daughter to come with him and bring my newborn infant granddaughter. His mother does not want him back at home with her and does not want my daugther and her granddaughter under her roof. His cousin couldn't help him and he is back in my home with my daughter and granddaughter. I want to keep my daughter and granddaughter and kick him out. How do I convince my daughter who is going to college to drop this guy? He curses worse then a sailor especially to his mother (who made up with him to see her granddaughter but does not want to be responsible for either -- that she will leave up to me is seems), He does not a job, nor seems interested in finding legitimate work. He smokes like a chimney, and has sticky fingers. Also, did I mention I am unemployed and divorced? To say I am angry is an understatement. I have never put my parents through anything that even resembles this situation. I need my daughter to stop being afraid of this man, and take my lead and get him out. I will kick him out, but I don't want my daughter letting him back in. How do I keep my family together without dealing with this unhealthy dead weight?