Property Disputes Regarding Apportion In Brother And Sisters

We are two brothers and two sisters. I am the youngest and all are married. My Father purchased a leased hold house from the housing board, Madhya Pradesh in 1999, with a lease period of 30 years and nominated my mother as she will be the owner of the house after his death. On that basis Mutation (Naamantran) in my mother's name was done Dec 2019 by the housing board and the lease renewed for 30 years and registered again because the lease was expired after my father's death. Now I am nominee in the new registry, My father died in 2012 without a will, now my mother wants to sell the house and wants to give all the money to me because my father was died due to cancer in 2012 and I am residing with mother, my elder brother has left the house in 2011. He was not willing to give any financial support in my father's treatment, he never gives any financial assistance to my father or mother to date, my mother is bed riddle for the last one year and I am the only one takes care of her.