Property dispute with sister in law

I am an unmarried only daughter of my deceased father and living with my mother in my father's self acquired property in Assam.i am currently unemployed. I have a younger employed brother married and living in Kolkata for years. He has his own acquired house there now. However all maintenance of my father's home and care of my mother is done by me solely with no financial contribution from my younger brother. Recently I got ill and had to leave my employment so my brother helped me with medicine bills from his salary per month. Now since our mother is sick he is again helping with a small amount of medicine bills for her. Currently due to huge expenditure made by my sister in law my brother is facing loan debts. As a result we have asked him not to send any money at all to us. However now his wife is pressuring us to give them the monetary value of my brother's share in my father's property either by mortgage of property or by immediate selling. He himself does not say anything but his wife has been threatening us through phone. My question is , can she sue us to forcibly make us sell or mortgage the property to give her husband's share of monetary value?