Sayyidah Umm Salamah (may Allah be pleased with her) said: "The Messenger of Allah (peace and blessings be upon him) and I used to take a ritual bath (ghusl) from a single vessel, which was about half a faraq (a measure); we would both take turns at the bath, and he (peace and blessings be upon him) would begin before me."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 20265