Rights of daughter on ancestral property.
My grandfather had 2 son and 2 daughter and had a property measuring approx 400 sq.mt with excess land in the same site. He died in 1965 without any will and in 1966 the land was mutated in my father and uncle name and around 3 years later the said land was subdivided and registered in my father and uncle name separately. In the year 1997 the youngest daughter of my grandfather filed a suit in my father and uncle name for her share in the said property and the elder sister declare in court that she has nothing to do with that property and will not spend any money on that nor she want the share.
Later in the year 2004 the excess land approx 450 sq.mt. was regularized and registered in my father and uncle name based on occupation right as per govt. rule. Now since the case was not going any where my father and uncle reluctantly agreed for compromise.
Now my question is can they sell the property with/without the consent of elder sister and divide the share between 2 son and 1 daughter. If the option is possible then what precaution we have to take to avoid any future complication. One more point i have to mention is since my father spend some amount to develop the site and construct a semi RCC house on that plot therefore asking for 40% share, uncle share 35%, Younger daughter share 25% and the same is agreed upon.
Family details Grandfather had 2 son and 2 daughter. 2 son and younger daughter had 3 children each, Elder daughter had 1 child.
So kindly advice on the above issue please.