Property Displute ?

My Grandfather had property in Gujarat and Mumbai. He had 5 sons all staying with their families seperately right from their marriages. One one uncke was staying in grandfathers house in mumbai from beigning. Now main cause is my dad was youngest amongst all of them and was staying seperate from them. My Grandfather had expired suddenly due to illness in 90's & my grandmother too expired in 2014, along with my father expired ayear later in 2015 due to TB. Now when i ask them about my right & share in property they say that they had given my fathers share with some documents made in court in gujarat, which was signed and accepted by my father then. They are not ready to give me any documents for the same which he has signed their in gujarat and neither they are giving my share in property. My question is can my daddy settle hjs share in property without concern of his childrens and wife and is it accepted by law with giving prior notice to his children and wife, Ok, even if we beleive he has settled his share in his property in gujarat, but what about his share in Mumbais property, can i file the case for share in grandfathers property here in Mumbai. Hkw can i get the cooy of documents also which they say they are signed by my father in gujarat. Also has grandmother any rights to not share the property wuth my daddy. please guidee as i m confused and aslonthe right way to claim the property.