Second wife Share in Govt employee property

Sir My Name is Ravi, I belong to Hyderabad,and my religion is Hindu. My father is Retd.Govt teacher. As my father didn't have children with his first wife, after waiting for 10 years (1969-1979), for the sake of children he got second marriage with my mother, without divorcing with first wife.And at the time of both marriages he was serving Govt employee(Teacher).Even after 9 years of second marraige born and i am a single child to my father among all of three of them.And all we lived&living together without any major conflicts. As It was part of continuing our linage my step mother didnot raised any objections for second marriage.And my father treated both of them equally without prejudice.While retiring from service my father has nominated my step mother(First wife) as official pensioner wife keeping in her livelihood in case of my negligence.And my father has earned the most of current properties(Land,House,FD) with his own earnings.Due to their bad financial situation there is no evidence of photo,video at my mother marriage. I am too married. currently all of us are living together under as my father as head of family. Now my question is ,In case in future ,If my step mother challenge the legality of my mother marriage with the father and my rights as legal heir of my fathers property,How strong her claims can be stand before court of law.can i claim 100% of my father properties as i am the alone successor of my father. 1)Ration card consists all of our family members(4),showing both of them as wivies to my father. 2)My own mother has some joint accounts with father, official nominees to some F.D.s 3)My identity certificates have some issues like Surname is missing in all of my identity,educational certificates due to some mistake while registrations , and same name is continued in all consequent documents.In my documents surnames of both of my father and mine are missing. 4)My father too have dual surnames recorded in different documents like joshi,& kulkarni. As He has Kulkarni in official service book, and as joshi in other identities like ration,election card ,aadhar card etc. 5)Except last 10 years (educational purpose )i along with my mother (to take care of me)were away from Home in Hyderabad ,. Are above points can be bottlenecks in proving our relationship.