Distribution of ancestral property & own father property

I am a central govt serving officer in Mumbai. Due to inter-cast marriage, my father did not have good relation with me. In the year Oct-2010 my mother expired at my native home at Kanpur. I was not informed but come to know from others after 2 months. When I reached at home, I was not allowed in the house by my younger son but threatened for life. I came back to Mumbai. I have come to know that after mother death, my younger brother sold whole property including ancestral & own by father during 2011-2012. I have also come to know that some of amount expended by my younger brother and balance deposited in bank in the name of my father with the nominee of son of my younger brother. My father has also expired in Feb-2015. There was no will or gift deed. Now, I or my son can claim equal share in the ancestral property and father's own property or can claim equal share on sale amount with up to date interest. If yes then how? let me know the procedure. We are 2 brother and one elder sister. Sister do not have any interest in the property. My relation is also not good with sister.