O Messenger of Allah, my nephew is ailing. So he wiped over my head and invoked blessings upon me. Then he performed ablution and I drank from the water of his ablution. After that, I stood behind his back and looked at the seal of prophet-hood between his two shoulder blades, and it resembled the egg of a pigeon

In this Hadīth, As-Sā’ib ibn Yazīd explains that his maternal aunt took him to the Prophet (may Allah's peace and blessings be upon him) and told him that he was ailing. So the Prophet (may Allah's peace and blessings be upon him) wiped over his head and invoked blessings upon him. Then he performed ablution, and As-Sā’ib drank from the water dripping from his blessed organs during ablution. Later, As-Sā’ib stood behind the back of the Prophet (may Allah's peace and blessings be upon him) and looked at the seal of prophet-hood between his two shoulder blades, which resembled a pigeon's egg.