Umm 'Ayyash, the slave woman of Ruqayyah, the daughter of the Messenger of Allah, said:
"I used to help the Messenger of Allah perform ablution, when I was standing and he was sitting." (RU)
English reference (RU): Vol. 1, Book 1, Hadith 392 (RU)
Arabic reference (RU): Book 1, Hadith 424 (RU)