(2351) Whoever things that giving water in charity, or as a gift or by way of a testament is permissible, whether it is divided or not
Narrated Sahl bin Sa`d: A tumbler (full of milk or water) was brought to the Prophet who drank from it, while on his right side there was sitting a boy who was the youngest of those who were present and on his left side there were old men. The Prophet asked, O boy, will you allow me to give it (i.e. the rest of the drink) to the old men? The boy said, O Allah's Apostle! I will not give preference to anyone over me to drink the rest of it from which you have drunk. So, the Prophet gave it to him.