Will vs gift deed...mothers want to transfer property

Hi, my grand father had a property and my father died in 2008. My buaji / I, my brother and sister made a reliqueshmnet deed in the favour of my mother in 2008 as the property is on my grand fathers name. Grand mother also died in 2004... now my mother sell that property and buy new house in 2016 on her name...she wants to transfer the property on my name but dont want to give anyyhing to my brother n sister.. whats d best way to trsnsfer d property??? A will or gift deed??? So no one can challenge especially my sister as she doest like me....my brother has no interest in that property....