The Messenger of Allah ﷺ said, "Whoever grants someone a lifetime gift, it belongs to the one to whom it was granted, both during his life and after his death. Do not make conditional grants, for whoever grants something conditionally, it follows the path of inheritance."
حدثنا عبد الله بن الحارث عن شبل عن عمرو بن دينار عن طاوس عن حجر المدري
قال رسول الله ﷺ من أعمر عمرى فهي لمعمره محياه ومماته لا ترقبوا فمن أرقب شيئا فهو سبيل الميراث
Its chain of transmission is sahih. Abdullah bin Harith is Ibn Abdul-Malik Makhzumi. Yaqub bin Shayba and Ibn Hibban both graded him trustworthy, and Ahmad and Abu Hatim approved of him. His hadith is found with the whole group except Bukhari. The hadith is like the one before it.