Sunan Abi Dawud Book 2, Hadith 323
"I used to be asleep while my legs would be in the front of the Messenger of Allah (ﷺ) while he was praying during the night. When he wanted to prostrate, he would prod my feet, so I would pull them up, and he would prostrate.
I used to sleep with my legs in front of the Messenger of Allah (ﷺ) when he would offer his prayer at night (i.e. tahajjud prayer offered towards the end of the night.). When he prostrated himself he struck my legs, and I drew them up and he then prostrated.
I used to sleep lying between the Messenger of Allah (ﷺ) and the qiblah. The Messenger of Allah (ﷺ) used to pray when I (was lying) in front of him. When he wanted to offer the witr prayer - added by the narrator Uthman - he pinched me - then the narrators are agreed - and said: Set aside.