Musannaf Ibn Abi Shayba 36:497

Ibn Idris narrated to us, from Isma'il, from al-Sha'bi, who said: The Prophet, may Allah bless him and grant him peace, was washed by Ali, al-Fadl, and Usama. He said: And Ibn Abi Marhab narrated to me that Abd al-Rahman ibn Awf entered the grave with them. Al-Sha'bi said: No one should attend to the deceased except his family. And in the hadith of Ibn Idris, from Ibn Abi Khalid: And Ali began to say, "My father and mother be sacrificed for you, you were pure in life and in death."