Can a married granddaughter claim share in grandfather's property

Respected Sir/Madam, I need help in understanding the law related to Married grand daughter's right on property earned by paternal grand father.My mother got married in 1985, my uncle (brother of my mother) says that my mother has absolutely no right on the property and he had all the property transferred to his name. He is threatening my mom to death if she even thinks of going to court for law on this issue when confronted him. He even sold some property with out my mother's signature. Please help me and my family to fight this case. We are very much worried about mother as my uncle is arrogantly mistreating her with threats.