Legal rights of a mother in law against daughter in law

Dear Sir, This is about my mother(widowe) who does not posses any property and completely depends on her only son (working as a senior sales manager in an mnc) but she is in a really bad mental stress because of the constant verbal abuse thrown at my mother by her daughter in law. She is constantly making all possible efforts and mentally torturing my mother as she does not want to keep her with them whereas my brother wants to keep my mother but does not have control on his wife.On the other hand,I am married and have a widowed mother in law who is dependent on my and my husband. Please help