Division of property

Good morning respected advocate who answer my question.after my grandfather's death;the property is being looked after by my grandmother since 2007. My grandfather has three sons and my father being the elder among them.since then my grandma started constructing a building in the name of development and took almost like 1core as loan from state finance corporation.apart from that she even used the money from outside at high interest rates where she was influenced by her younger side by keeping aside the rest two.they were unable to pay the loan and started seeing the lands what we have.actually here there is a small problem like that building was actually looked up on by my father as it was dedicated to my father Benji's father.the younger son setup a factory by mortgaging the house papers....they are gradually selling the lands and in future we might be worrying that we would not get any thing...the younger son have used a lot of money from my grandma but she hid it with everyone...and moreover when we started demanding for the share of the property she is demanding a 4th share...we are known that even the 4th property would be given to the younger son...what is the solution for this .how should we deal with...my father is absolute silent as he don't want to loose out the reputation of the family...but no one is considering my father's silence as taking that silence as useless.she has water by giving a lot of money to the younger son...we are in need of money as we want ed to pursue education...my father is 50 and hebcant earn as the strength of working outside will be gradually decreasing...we need a solution for this respected advocate..