Idris bin Muhammad narrates from his grandfather, who narrates from his father, Sayyiduna Muhammad bin Fadalah (may Allah be pleased with him), who said: The Messenger of Allah (peace and blessings be upon him) came to Madinah when I was two weeks old. I was brought to him (peace and blessings be upon him), and he (peace and blessings be upon him) passed his hand over my head and said: "Name him with my name, but do not give him my kunyah." And at the Farewell Pilgrimage he (peace and blessings be upon him) took me with him on Hajj when I was ten years old. He said: Muhammad (may Allah be pleased with him) lived so long that his head turned white, but the spot where the Prophet (peace and blessings be upon him) had placed his hand did not turn white.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16596