Ask your father about how he purchased the property. There must be some documents.

u need to gather proof of the fact that the house belonged to you or your father and after that only, you can file a suit. unless you prove your title, how can you challenge someone else's possession or ownership.

Your father should have some documents related to that house showing that you r owner. only then you can take any step till then dont made any reply to the case file by your uncle son. Or first send your PM at my mail

Regards

adv.kamal.grover@gmail.com