Self earned property dispute

Hello, My grandmother have had some self earned property (land) which she gave to my father and uncle by will before her death. We have that will with us. When my father and uncle went to registar's office to transfer names on this property, officer sent notifications to remaining children asking if they have any objection to such transfer, to which my paternal aunty responded and objected to transfer and asked for her share in property. My other uncles did not raise any objection as they have already got their share in some other property of my grand parents. My questions are - (1) - If property is self earned and by will it is given to specific children, whether "no- objection" is required from other children? If yes then what is the solution for above dispute? (2) - My father and other uncles had given some amount to aunty as a compensation of property share in 1991 and she had given in written on 50Rs bond paper that "Henseforth she has no claim on any property of her parents", but it was not written in front of any lawyer or notary. Does that bond paper holds any value in legal terms which we can use against her claim on proerty? Thanks and Regards, C V Jayawant