1, It is not ancestral property, it is yor grandmother's own and absolute property.
2. Yes, she can very well dispose the property in the manner she thinks fit.
3. She can write a will bequeathing the property to anyone of her choice, the other person cannot claim a share in it as a right.
4. You dont have any rights in the property hence dont waste time, energy and money by filing a frivolous and untenable suit seeking any share in the property.
5. Even if your mother was alive, she has no rights over the property that belongs to yor grandmother.Therefore you do not have any rights in the property.
6. Yes, it is your grandmother's own desire and discretion to divide the property in the manner and method she would like it to be distributed.