What is the legal right of second wifes son on the property of first wife?

I would like to know what is the legal right of my i.e son of second wife on the property of first wife of my father. A long time ago my father brought a house/ansectral house and he registered in the name of first wife. After death of first wife he married with my mother i.e my father's second wife. Now my father dead. My brothers are (fathers first wife's sons) are not giving the share of the house to my. So I would like to know what is the legal right of me and my mother on this house.