Right of grandfather property to grandson

Hi My Grandfather's property is in Dharmapuri, Tamil Nadu, after his death, the property was transferred to my grandmother! They have one elder son, who is my father and five sisters, the husband of last sister convinced my innocent and illiterate grandmother and transferred the entire property to his wife without the knowledge of my father who holds responsible for the property! After this incident, my father cancelled the old registration and transferred back the property to his name as family settlement and later settled the shares to all his sisters! Being a retired deputy director, central government employee, he has sold already his self acquired property worth of 30 lakhs about 10 years back and no one in our family knows where that money gone, he has sold worth of 70 lakhs from grandfather's property in a period of about 10 years and no one in the family knows where that money gone, his retirement benefit in 2013, hopefully 40 lakhs would be received and no one in the family knows where that money gone, he never supported for the family, no wealth creation, not even a single piece of asset created till date and still paying about a lakh as interest for his personal hand n bank loans, we have been raised with full support of our mother, who is a state government employee! Doubting on his activity and enquired with his close friend who is a lawyer, I come to know that he was a gambler! Now my father keep selling the ancestral property which is left without our knowledge, kindly suggest me that, if the grandfather's self acquired property was not given by will to his son, do i have right to claim? Thanks in advance!