Clarification on the property law on the gifted land

Hello Sir/Madam, I have a doubt regarding the transfer of property in the form of gift. Kindly clarify. My grandmother and her 2nd son(my father is first son who expired 2 years back) had sold a property of 1 acre in 2003, without my father's knowledge, which was acquired from my grandfather. He was out of the country at that time. Few years later, he came to know about the sale of land and did not take any action on them and during the family partition in 2005 each of the son got 2 acres of land and they left 2 acres of land on my grandmothers name(which she acquired from her parents). Now the same land has been written to her second son in the name of gift, in April 2017, after my fathers death. Please let me know if I will have an equal right on the above mentioned property and if I can fight a legal battle with them on this 2 acres land my grandmother gifted, and also on the land they sold without my fathers consent in 2003. Please suggest how to proceed. Regards Sandeep