Sahih Bukhari Volume 4, Book 56, Hadith Number 741.

Narated By As- Scab bin Yazid : My aunt took me to Allah’s Apostle and said, “O Allah’s Apostle! My nephew is sick”‘ The Prophet passed his hands over my head and blessed me. Then he performed ablution and I drank the remaining water, and standing behind him. A saw the seal in between his shoulders.”