Can we can take back a Gifted Property after the receipt died

While the brother (45 years) was on the death bed from Cancer, my wife has gifted (with NO condition) her share of the inheritance property (no will left by father) to her dying brother hoping that he will recover by the happiness of receiving the property. However, he passed away within two months. Now the wife of the deceased brother is trying to sell the property. My wife has so much emotional attachment to the property because her father and grandparents spent a lifetime building such legacy and ancestral properties. The wife of the deceased brother hasn’t registered the property in her name yet. Is there legal action my wife can take to take the property back. Can she execute any actions without the knowledge of the wife of the deceased. All my wife wants is to protect the family properties beyond this generation. Please let me know what are the actions, how, and associated legal cost (stamp paper etc) of such actions. Thank you in advance for your kind guidance.