Your Aunts have equal share in Grand fathers self acquired property.In Ancestral property ,First you have to check the property is ancestral or not?
What is ancestral property ?
Property inherited upto 4 generations of male lineage (i.e., father, grand father, etc.) is called as ancestral property. The right to a share in such a property accrues by birth itself, unlike other forms of inheritance, where inheritance opens only on the death of the owner. The rights in ancestral property are determined per stripes and not per capita. This means that the share of each generation is first determined and the successive generations in turn sub divide what has been inherited by their respective predecessor.
Properties inherited from mother, grandmother, uncle and even brother is not ancestral property. Property inherited by will and gift are not ancestral properties. Self acquired property on the other hand can become ancestral property only if it is thrown into the pool of ancestral properties and enjoyed in common. This is a matter to be determined on the facts and circumstances of the case.
The Supreme Court of India has said that women do not have the right to inherit ancestral property if their fathers died before September 9th, 2005. The view of the Supreme Court is that amended provisions of the Hindu Succession (Amendment) Act, 2005, do not have retrospective effect. The father would have to be alive on September 09, 2005, if the daughter were to become a co-sharer with her male siblings.Until this judgment by the Supreme Court, women could not ask for a share if the property had been alienated or partitioned before December 20, 2004. But now, the court has made it necessary for the father to have been alive on or before September 9th, 2005 for the daughter to claim her right in the family property.
If it is not ancestral property ,your aunts have equal share in the property after the death of their father.