Settlement deed

My father purchased one ground land through absolute sale deed. Due to health conditions my father made a settlement of the above land to my mother through settlement deed and registered it. Now my mother is expired. I am the only daughter and there are three brothers to me. Now my father is 80 years old, staying with me and my brothers do not care about him. Now my brothers ( legal heirs) are not agreeing to sell the land which is on my mother's name. My father has spent huge amount for my mother's medical treatment . Is there any chance to get back the above land to my father's name by cancelling the settlement deed which was exclusively done for my mother ? Or can my father and myself sell our undivided share of land ? Legal heir certificate shows 5 members ...father, daughter and three sons. My father made the settlement deed only for my mother, considering his health. Now my mother is no more. Father is suffering a lot, by age, health, wealth, finance, loans etc. Is there any possibility to get back the land by cancelling the settlement deed ? Is there any possibilities to sell his share of undivided land ?