Husband Second Marriage Issue

My sister married 2010 having two daughters 12 and 9 yrs of age. My brother-in-law second married without any concern of my sister. He has attempted couple of times earlier and warned at the police station for the same issue. Considering the future of my sisters daughter she has not filed complaint during the time. Third time brother in law married and disappeared for a month after an year he appered with baby for his second wife,these happed with the support of his parents and uncles. Even that time, my sister decided not file a case against for his second marriage. Now after couple years they step by step increased the trouble to leave the house by mother in laws. Because my sister residing at their ( mother in law property) where they lives together living before the issue. My sister's mother in law and her sisters are troubling and harming children's to leave the house. They have some property and current house with some rental income from that right now. But it's in the name of her mother in law. What can be the next step to make an advice to my sister for the safety of my sister and her daughters. Kindly advice, is it possible to tranfer the current property to my sister's daughter name by legal way. Kindly advice the possible legal ways.