Agriculture property related query

Hi Team, My mother has agriculture land in her name as per will written by her mother, but now my mothers brother is asking for part in it. 1. Now agriculture land is going to be acquired by government and my mother has received 2 notice from government and another 2 notice will be there and than land will be acquired by government. 2. In the mean will my mothers brother has sent legal notice for half part in land. 3. Does the acquiring of land will be stopped for my mothers land. 4. Or if land acquired by government than can we claim half of the compensation provided by government.