Land sale amount distribution

Hello sir, I am Amanulla from AndhraPradesh. We have an issue of land. Details of the issue:- my grand father has 2 daughter And 3 sons . My grandpa was a government teacher. Before his death he was suffering with paralysis. 2 of his sons was govet employs. 1in food corporation 2 in army. When my grandpa died his family was in very poor condition, one daughter was married, 5 years After death of my grand Paa, his three sons purchased 6 cents of land with their own money on the name of their mother(my grand ma). When they are purchasing son in-law of my grand ma came and by force register 3 cents of land on his name by saying u don't require 6 cents give me 3, and regester by force at that time, and he don't even pay us a penny, today we sale our 3 cents land which we construct a house. Now due to land was registered on my grand maa name, all 5 members came and signed on the sale documents, and now two sisters demonding us equal share, we went to their home and requested them try to give some amount but they refused and herashing us and black mailing us. They trying to put criminal case on us, first they called us to police station forcefully by one of their son runs a weekly news paper, and ask us money, we told this property was our not their property, due to property was on my mother's name so all came to sign in regester office and signed, we try to given money but they refused. S.I told this is a civil dispute you should go to court, on that day in police station their son recorded an audio in a phone recorder (it's not a call) option in his phone and blackmailing us that he will put us in jail with this evidence. Now We are not understand what to do. They print a stories onus in his news paper and blackmailing us, even they try to brake my sisters engagement by saying that she is a prostitute type girl, we are afraid Please suggest us some laws which protect us from this devil's. Is their recording valuable ? Please help in to protect our selves to save from them