Musnad Ahmad 28:271

'Abd al-Wahhab al-Khaffaf narrated to us, Husayn narrated to us, 'Amr ibn Shu'ayb narrated to me, from his father, from his grandfather, that a man asked the Prophet, peace and blessings of Allah be upon him, and said: "I have no wealth, and I have an orphan." He said: "Eat from the wealth of your orphan without being extravagant," or he said: "And do not ransom your wealth with his wealth" — [Husayn was] in doubt.