A property registered in the name of a female (Hindu), will be her absolute property under sec14 of Hindu succession act.
The woman (mother in law) can deal with the property in whatsoever manner she deems fit during her life time. She can give it as Gift/ Sell it to any person whom she desires.
Mother in law need not get any approval from any of her children to deal with the property during her life time.
However in the event of untimely demise of the woman and in the event of she not leaving behind a WILL, the property will devolve on her legal heirs equally.
The act is reproduced here for your perusal
Sec 14 of Hindu Succession Act.. Property of a female Hindu to be her absolute property
(1) Any property possessed by a Female Hindu, whether acquired before or after the commencement
of this Act, shall be held by her as full owner thereof and not as a limited owner.
Explanation: In this sub-section, "property" includes both movable and immovable property
acquired by a female Hindu by inheritance or devise, or at a partition, or in lieu of maintenance or
arrears of maintenance, or by gift from any person, whether a relative or not, before, at or after her
marriage, or by her own skill or exertion, or by purchase or by prescription, or in any other manner
whatsoever, and also any such property held by her as stridhana immediately before the
commencement of this Act.
(2) Nothing contained in sub-section (1) shall apply to any property acquired by way of gift or under
a will or any other instrument or under a decree or order of a civil court or under an award where the
terms of the gift, will or other instrument or the decree, order or award prescribe a restricted estate in