بسم الله الرحمن الرحيم
Until the father is alive he alone is the owner of all his property. He can do whatsoever he wants in it. If he, in his lifetime, gifts each of his children (sons and daughters) one-one flat from eight floor building and gave the flats in their possession and withdrew his ownership from the flats then this gift (hibah) was valid and each son and daughter became the owner of his or her share. The objection of the wife’s brother is not correct. Whatsoever you expressed your views it is correct according to Shariah.
Allah knows Best!
Darul Uloom Deoband
This answer was collected from the official ifta website of Darul Uloom Deoband in India.