Ibn 'Abbas (May Allah be pleased with them) reported:
The Prophet (ﷺ) came across a caravan at Ar-Rauha' and asked who the people in the caravan were. They replied that they were Muslims. They asked: "Who are you?" He (ﷺ) said, "I am the Messenger of Allah." Then a woman lifted up a boy to him and asked: "Would this child be credited with having performed the Hajj (pilgrimage)?" Whereupon he (ﷺ) said, "Yes, and you will have a reward."[Muslim].
App reference: Book 11, Hadith 12
Arabic/English book reference: Book 11, Hadith 1282