Can son/mother claim property/security from separated father

Hi, i am 23 yrs old female. My parents had disputes due to which they saperated but not divorced. We have been living in the same house on differrent floors. He doesnot support us financially. The property that we have been living in for past 20 years is on my grandfathers name. We are not sure about our father's and paternal side family's intentions as they have already sold our ancestral property without our knowledge and want to secure ourselves. I have the following questions 1. Can my mother claim any kind of financial security from him now? 2. As the property is on our grandfather's name, my father as well as his brothers and sisters hold share in it, i have one brother only do we also hold share in it?