share in grandfathers property

It is a property under inheritence. Ur mother needs ur consent to forgo the rights. If ur grand father died b4 u were born or u were actually conceived, the case cud hav been different. U can approach a civil court of appropriate jurisdiction. This is my opinion. U shall verify it to ur satisfaction

First we have to know whether the property is ancestral or self acquired one. If the property is ancestral, then your mother has equal share in the property along with her siblings and her mother. So, your mother and your aunt both are entitled for 1/7th share each, in the property. You inherit the property from her. If your mother does not want to take her share, she has to give relinquishment of rights deed. Then the property will be divided equally among remaining siblings of your mother.