From Sahih Muslim (Hadith 7358):
Ibn 'Umar reported that Allah's Messenger (ﷺ) happened to pass by Ibn Sayyad along with his Companions including 'Umar b. Khattab as he was playing with children near the battlement of Bani Maghala and he was also a child by that time. The rest of the hadith is the same as narrated by Ibn Umar (in which there is a mention of) setting out of Allah's Apostle (ﷺ) along with Ubayy b. Ka'b towards the date-palm trees
Reference: Muslim 7358