Musannaf Ibn Abi Shayba 35:478

Al-Hasan ibn Musa narrated to us, Zuhayr narrated to us, from Abdullah ibn Isa, from his father, from his grandfather, from Abu Layla, who said: I was with the Messenger of Allah, may Allah bless him and grant him peace, and he stood up and entered the house of charity (bayt al-sadaqah). The boy—meaning Hasan or Husayn—entered with him. He took a date and put it in his mouth. The Prophet, may Allah bless him and grant him peace, extracted it and said, "Indeed, charity is not lawful for us."