Hadith #5931 (Sahih Muslim)
Book: The Book of Virtues
Narrator(s): As-Sa'ib bin Yazid
Grade: Sahih

My mother’s sister took me to Allah’s Messenger (ﷺ) and said: Allah’s Messenger, here is the son of my sister and he is ailing. He touched my head and invoked blessings upon me. He then performed ablution and I drank the water left from his ablution; then I stood behind him and I saw the seal between his shoulders.

Source: https://parallelquran.com/hadith/sahih-muslim-5931/