"The Messenger of Allah came to me one day looking happy and said: 'O 'Aishah! Did you not see that Mujazziz Al-Mudliji came to me when Usamah bin Zaid was with me. He saw Usamah bin Zaid and Zaid with a blanket over them; their heads were covered but their feet were exposed, and he said: These feet belong to one another.'"
Sunan an-Nasa'i Book 27, Hadith 106