Sahih Muslim Book 41, Hadith Number 7001.

Abdullah b. Umar reported that Allah’s Messenger (may peace be upon him) went along with him in the company of some persons and there was Umar b. Khattab also amongst them till they saw Ibn Sayyad as a young boy just on the threshold of adolescence playing with children near the battlement of Bani Mu’awiya; the rest of the hadith is the same but with these concluding words: “Had his mother left him (to murmur) his matter would have become clear.”