Property Disputes Regarding Apportion In Brother And Sisters

My father bought one house on lease from the housing board Madhya Pradesh whos lease is expired on 2008 and father died in2012 without a will and nominate the mother in the sale deed that she will be the owner of the house after his death on that basis mutation and new registry and lease is paid my mother in Dec 2019, the nominee is me. We are two brothers and two sisters. Now mother wants to sell the house wants to give money to me and my brother left our home in 2011 and never give any financial support to father when he was suffering from cancer and mother too and also harassing mother building pressure on her about giving his part, in 2013 he was done false complaint to police about me. Now he is given notice through an advocate to my mother about his partition among brother and sister and harassing mother she is on the bed she is not able to walk from last one year due illness sir tell me what strict action to be taken on behalf of my mother legally, please suggest me