Can grand daughter claim assets from grand mother.

Dear Sir, I have registered all my properties in my mother name, house, plot, agricultural land etc., in Tamilnadu. My father passed away - none of the property was in his name, even when he was alive. My mother is living - all my properties I had registered in my mother name. For my parents me and my sister only children. My sisters daughter is married and We want to know whether she is having any right to claim the family assets which is my mothers name(means that granddaughter can claim from her grandmother's property). My mother forcing me to register everything back in my name, since I live abroad, I want to know the legal system. If my sisters daughter doesn't have any legal entitlement then I don't want to register any thing. If required my mother can write a will. Can Grand daughter can claim assets from grand mother. What if grandmother wants to give the property to son. What is the status after the grand ma. Who all will be legal heirs. Need a legal consultant opinion. Thanks Thanks & Regards, Mahesh