Custody and domestic violence.

My sister is going through a bad marriage in Bangalore. She got married 1 and half years back and has a baby girl of four months. Her husband and mother in law do not let her speak to her family and prevent her from meeting her family(parents and sister /brother in law). She has not complained of physical violence so far but he verbally abuses her and threatens her to leave the house if she does not listen to her. He did not let us see her daughter. She is very scared of her anger.

My father has undergone a bypass surgery two days back. He is not allowing her to come and see him without his permission. Today she tried to walk out of the house but he did not allow her to take her daughter. He threatened to leave her take away the daughter to Delhi to his mother. She got scared and went back. I asked that should we intervene but she is so scared of him that she does not let us talk to threaten him. She is working and financially independent. Pls advise what shud we do? Can he take away the baby to Delhi. What if she leaves the baby and comes as he is not allowing her to bring her along. Can she fight for the custody?