Partition of House- My father is in undue influence

If it is an ancestral property inherited from your grand father then you can ask your share in your father's share in the house .  In the house your father will get 1/3rd share in that 1/3rd you will get your share along with your mother and other brothers and sisters.

Sir,

   What if my father signs a document that he is no longer intrested in property? Subsequently will I too loose my share? The house is ancestral property i.e made by grandfather and he is alive as well. But he has made the ownership in name of my father and uncle already. But my father says he will give it back to my uncle. 

Please clarify whose house is this?