IM now at nearly 70 age, recently i came to know that My cousin brother(my father's brother son) sold his one acre of land to his best friend on 01.02.1965 for Rs. 5,000. The person who purchased his land paid only Rs.2,000 but he did not fully paid the remaining amount (Rs.3000). On the same day (01.02.1965) the person who purchased his land mortgaged entire land about one acre to my cousin brother(seller of the land). My cousin brother (Seller) and his wife dead recently, my cousin brother did not have any children. But the buyer/Mortgagor(also died) and his childrens sold some part of land and remaining part of land they are going to sell in future. During 1965's my cousin brother was cheated by his friend to sell his land to his best friend, my cousin brother was not educated. My question is
1.Is there any possibility to recover the land one acre. ?
2. can i be the legal hair for my brothers property ?