Musnad Ahmad 744:2

Waki’ narrated to us, Sufyan narrated to us, from ‘Ali ibn Zayd ibn Jud’an, from Zurarah ibn Awfa, from ‘Amr ibn Malik—or Malik ibn ‘Amr, that is how Sufyan said it—he said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever takes in an orphan between his two parents, then Paradise is certainly his."