Advice

My sister recently moved home from her bf's that is a few hours away. She had a miscarriage & was becoming depressed. They were going to work it out, but he started constantly asking where she was & checking her Facebook messages. She found out she was pregnant after coming home. He started  harassing her nonstop. They broke up. He is still constantly messaging her so she blocked him on messenger. She is done & basically wants him to have nothing to do with the baby. She is concerned about his mental health issues, his family's mental/drug issues, etc. she was going to try to work with him, but he freaked out saying that he didn't want to be separated from the baby. He's acting like the victim to all his friends/family.   We're concerned about another miscarriage too, so she's just trying to take it easy. I don't know what is the best thing to do is, I don't want to give her the wrong advice. Should she continue to try to talk to him or should she continue to block him & wait for court?