Ancestors Land

My ancestors ( grandfather and his family maybe relatives shareed equal distribution of property land). My grandfather passed away in 2006 and he has 4 sons including my father. My grandfather relatives (the shareholders) has two sons. There is a land in road side area. The govt.of bihar bought some land between my land for canal making purpose making the land into two parts( govt. Give the money equally to both the family). My grandfather relative are demanding the roadside areas portion, selling it without our constant and without new distribution after the canel was made. Questions are 1). Can they totally sell the land from roadside area as it has more value than the land behind canel??? 2). If they somehow manage to sell, do we have to ( my father and uncle) has to get the land behind the canel? Is it legal for them to sell the land without our consent? Can we get equal proportions of land from roadside area as which means front of canel as well as from behind the canel?? Is them selling the land without our consent currently prevent us from getting equal proportions in future? Please note- we do not stay in same as our native place hence it is hard for us always to go back and have discussion on same. The moment we returned to our business place they start to sell land or anything without our consent.