1) your mother cannot cancel the gift deeds unilaterally
2) the Supreme Court has held that a minor could legally accept a property gifted to him and the gift-deed executed in his favour in this regard is irrevocable.
A Bench comprising Justice Y.K. Sabharwal and Justice D.M. Dharmadhikari pointed out that Section 127 of the Transfer of Property Act clearly recognised the competence of a minor to accept a gift.
The Bench said "when a gift is made to a child, there is a presumption of its acceptance because expressing acceptance in his case is not possible and only an implied acceptance can be expected".