Grand father's property needs to be divided or sold

Hi, This is for my Uncle's (father-in-law) property related.. My Uncle's father was died intestate/without executing the will in 1980. He got this property from his father (Which is actually keep coming from great grand fathers). He has 5 sons (including my uncle) and one daughter, one of the brothers has died who has two sons. Property is about 3 acres of land. Question 1 : My Uncle's father had only pass book, EC shows NILL since this property doesn't have any trasactions as got it from great grand fathers. My Uncle and his brothers have been paying taxes on this pass book but never took his death certificate till now (this is biggest concern). How would this proptery be possessed and divided among legal heirs (and sell out if they want) Question 2 : Another part of the property (13 cents) was taken on the name of my uncle's mother and his sister. Which was registered as 8 cents and 5 cents to his mother and sister respectively on a combined land. his mother was died and has death certificate. How would this proptery be possessed and divided among legal heirs (and sell out if they want)