Create documents for inherited property which is not documented.

Good morning to all Im a resident of Tamilnadu belong to Hindu community. My father born with three sisters and two brothers. Partion took place in 1968. Before that all my father sister got married and settled eleswere. One brother and two sisters died. The problem is now my fathers younger brother died two years before who was a widower no sons or daugthers. He was living alone in a house given by his parents while partition. He left no will. There were some debts for which our father paid it and got the documents signed by him. Now the property is without any document and want to ask if one his sister who is still alive can claim the rights. My grand parents died 15 years before. I as a son performed all final rituals and the house is in my possession. how can be a document created by me for that. I have his death certificate issued by VAO . Presently all the taxes have been paid by me. I want to do some renovation work for which i need to apply for loan. kindly help