My Late Father in Law has 3 sisters. so inherited property has 4 shares ( Late Father in law and his 3 sisters). 3 of the sisters recently made a gift sale deed and given their persoanl share to my brother in laws wife to avoid despute with cousins brother & sisters of Late Father in law. now my brother in law has passed away 2 months back. and his wife is not in good terms with my widowed mother in law. she is planning to sale the property to some 3rd person secretly and give up all relationships with my mother in law. please kindly suggest how can the gift sale deed be cancelled between my late Father in law's 3 sisters and my late brother in laws wife?
is there any other means for doing the same?
Thank you.