How get my land registry as a legal heir

My grandfather had a land measuring about 10 katha. He had his wife 3sons 4daughters. He died somewhere back on 90's. After his death in the crisis situation grandmother sold 3katha land to meet the needs of the situation by receiving the power of attorney from all sons and daghters. After some years all the children got married and were busy setting their lives. Meanwhile somewhere back between 2002 to 2004 one of the son took 2katha land and of the daughter took a small place from this property to open a shop registered in their name as gift deed without anyone knowing about it as the power of attorney was with the grandmother herself. My father died on 2007 leaving behind the legal heir as my mother, my brother and me. On 2011 my grandmother also died. Now we want to get our part registered from that property. But one of the daughter who has already taken a place for shop from that property is claiming some money or part land to give her sign. Now that the new law is passed by the supreme Court. According to this will daughter get any part from this property or is their signature required to get my share of land registered from that property. If so then please suggest me how can i solve my problems immediately..