Asigned land in between brothers

I Rajesh Derangula, my grandfather D.Pullaiah(Elder brother) and D.Anthony(younger brother) are two sons of D.Veera Swamy. He got assigned land about 4.5 acres in around 1960's from government. Both sons got married and divided the land equals shares to sons to an extent of acres 1.81 to elder one Pullaiah and 1.81 acres to younger one. Later on younger brother got son for his first wife, he left his first wife and adopted his son to elder brother Anthony. Anthony sold away his share to elder brother Pullaiah in 1981 for sum of consideration in front of villagers with all necessary agreements. Later Anthony get married another woman in 1981 settled in another place. Now he got two sons and daughter. With influence of his sons he approached the court, argued that transfered land is not legal, it should be reversed to him. Regarding the pattadar passbooks issued in 1994 in the name of Pullaiah and adopted son Venkata Rao. The same land enjoying by legal heirs from last 40 years.