Ancestral Property

My grandmother passed away 6 years ago without leaving a will and is survived by two daughters and husband too. The property was a two floor building of which the bottom portion was used to take a loan and marry the oldest daughter of my grandmother. The interest on the loan was for a long time paid by my grandfather (husband of the deceased) and the youngest daughter (my mother) until they couldn't anymore and decided to sell it which settled the loan and interest. First thing I wanted to know is whether the house will now belong to my grandfather? He is staying alone in the same house and alternating between the older and younger daughter for few months each. Second thing was I wanted to know how the property would be divided as my grandmother's older daughter now wants to sell it and take her share of the top portion even though the bottom portion of the house was sold only to be able to marry her then. a) Is she eligible for a share? b) If my grandfather cannot have the house transferred to his name and it has to be split then will he be eligible for his share.