Anas (May Allah be pleased with him) reported that he passed by some children and greeted them. Then he said:
"Messenger of Allah (ﷺ) used to do the same."[Al-Bukhari and Muslim]. (PT)
App reference (PT): Book 6, Hadith 18 (PT)
Arabic/English book reference (PT): Book 6, Hadith 862 (PT)