Mishkat al-Masabih 476

Al-Sāʾib ibn Yazīd said: ‘My maternal aunt took me to the Prophet and said: “Messenger of Allah, my sister’s son is ill.” He wiped my head and prayed for blessing for me. Then he performed ablution, and I drank some of the water from his ablution. I stood behind him and saw the Seal of Prophethood between his shoulders, like the button of a bridal canopy.’