Volume 8 · Book 75 · Hadith 365
Narrated Mahmud bin Ar-Rabi: On whose face Allah's Apostle had thrown water from his mouth, the water having been taken from their well while he was still a young boy (who has not yet attained the age of puberty).
— Sahih Bukhari, Volume 8, Book 75: Invocations, Hadith #365