Dear Mr. Santhusen8,
All that has been done (both by you and by your aunts) are completely wrong.
1. Please understand, that the properties in question are your grand father's self-acquired property. Since he did not leave any WILL/Gift Deed, the property, upon his death will get inherited equally by all his legal heirs viz., your grand mother, your father, your father's brother, your father's all three sisters.
2. Therefore, it is not clear how your father got the property registered in his name in the year 1999. (This cannot at all be done, unless your grand mother, and other legal heirs give a registered relinquishment Deed in favour of your father. You say that "we did not take any relinquishment deed from my aunts". Therefore such a registration in your father's name, without giving the property to others is not at all correct and legal. You also asy that your grand mother has signed our shares. At best, your grand mother can relinquish her share in the property in your favour, but she has no right to do so on behalf of her daughters.
3. Your grand father spending money on the marriage of your aunts etc., will not count. Similarly, your grand father also gave food and shelter to your father and your father's brother. So what. Those are all his duties. The fact is, when your grand father died, he left some property. He did not leave any WILL/Gift deed. Therefore, the property has to go equally to all his legal heirs. Your aunts can claim it at any point of time. There is no time limit at all. If any of the lawyer has said that they should ask for their share within 2 years or three years, then he is grossly misleading you.
4. Now, you say that your aunt has sold some property (her share) to a third party. This is illegal. For she could not have sold the property without proper partition. She will not be able to say which portion she sold.
5. Giving dowry, performing the marriage etc., etc., will have no bearing on this matter.
6. Further more, the statement of MIL/FIL of your aunt's that they took the amount during marraige etc., will also not be of any help. They are nobody to make such statements. They have not been authorised by your Aunts to say so. It is your aunt's who have to say and they are not saying so. Therefore, you will not be able to get any benefit from the statement of the MIL/FIL of your Aunts. Your Grandmother's support is also of no use.
7. The correct position for all of you to do is to now sit and first agree to partition the property amongst all the legal heirs of your grand father. After such partition, get the partition deed registered. Thereafter get the respective portion of the property duly mutated in each one's name. Only thereafter, one can sell his portion and nor before it.