Unilateral Cancellation Of Property Due To Queries In Property Dimensi

My mother is an Hindu women and made a gift deed to her sister on 2007.The property was earned by my father. Earlier out of 2376 sq. ft 1650sq.ft was given to my brother on 2003 and the said gift deed was executed for 1256. As per remaining assets my mother is laible to give only 726sq.ft, the gift deed was executed without my father and brothers concern. Later knowing the fact my mother cancelled the deed stating the above said reasons and tax. Eb being in my mothers name. The property was partly possessed by each other. Earlier to this we moved to rdo court and got the patta cancelled back to my mothers name. Under this circumstances does the unilateral cancellation is valid or not. We have a concern written by apponent and certified by notary. Please give your suggestions.