Sahl bin Sa'd (May Allah be pleased with him) reported:
A drink was brought to the Messenger of Allah (ﷺ) and he drank some of it. On his right was a boy and on his left were elderly people. He said to the boy, "Would you permit me to give the rest of this drink to these on my left?" The boy said, "O Messenger of Allah, I would certainly not give preference to anyone in anything that might come to me from you." So he handed over the rest of the drink to him.[Al- Bukhari and Muslim].
Arabic/English book reference: Book 1, Hadith 569