What are the rights of children on fathers property

The property i am talking about is of my grand father who had three son's and the property are divided equally to 3 of them . And my father as six daughters my grandfather and grandmother passed away and all the six daughters are married . Now my father health condition is bad so we are looking after him . Now does my father as more rights on the property that came from my grandfather to him or my sister and me have more right to take equal parts in the property (1/6 parts) . And does my father have rights do will on this property by writing it to single daughter or to my mother's name