Abu Hazim said: I heard Sayyiduna Sahl bin Sa'd (may Allah be pleased with him) say: A cup was brought to the Messenger of Allah (peace and blessings be upon him), and he (peace and blessings be upon him) drank from it. The elders were on his (peace and blessings be upon him) left, and a boy, the youngest of the people, was on his right. When he (peace and blessings be upon him) had drunk, he said: "O boy, will you permit me to give it to the elders?" He said: O Messenger of Allah, I will not prefer anyone over my share of what is left over from you (as a blessing). So he (peace and blessings be upon him) gave it to him.
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 5794