Sa'd bin Ibrahim سعد بن إبراهيم بن عبد الرحمن · The Book of Purification

It was narrated from Al-Mughirah bin Shu'bah that the Messenger of Allah (ﷺ) went out to relieve himself, and Al-Mughirah followed him, (carrying) a vessel of water. He poured water for him when he had finished relieving himself, and he performed Wudu' and wiped over his Khuffs.