Musnad Ahmad 25:1310

Muhammad ibn Ja‘far narrated to us, Shu‘bah narrated to us, from al-Hakam, from Sa‘id ibn Jubayr, from Ibn ‘Abbas, that he spent the night at the house of his maternal aunt, Maymunah. The Prophet, peace and blessings of Allah be upon him, came after the late night prayer (al-‘isha’ al-akhirah) and prayed four rak‘ahs, then he slept. Then he stood up and said, "Has the boy slept?" — or a word similar to it. He said: So he stood to pray, and I stood to his left. He took hold of me and placed me to his right. Then he prayed five rak‘ahs, then he slept until I heard his snoring — or his heavy breathing. Then he went out to pray.