Musnad Ahmad 1153:2175

Hammad ibn Khalid narrated to us, he said: Layth ibn Sa’d narrated to us, from Mu’awiyah ibn Salih, from Yahya ibn Sa’id, from al-Qasim, from ‘Aishah, she said: She was asked: "What did the Messenger of Allah, peace and blessings of Allah be upon him, do in his house?" She said: "He was a human being among human beings; he would pick lice from his garment, milk his ewe, and serve himself."