The Messenger of Allah ﷺ said, "Every child is born upon this fitrah. It is his parents who make him a Jew or a Christian. It is just like the camels you breed. Do you find any among them with cropped ears until you crop them yourselves?"They asked, "Messenger of Allah, what about one who dies while still a child?"He replied, "Allah knows best what they would have done."
وقال رسول الله ﷺ ما من مولود يولد إلا على هذه الفطرة فأبواه يهودانه وينصرانه كما تنتجون الإبل فهل تجدون فيها جدعاء حتى تكونوا أنتم تجدعونها قالوا يا رسول الله أفرأيت من يموت وهو صغير قال الله أعلم بما كانوا عاملين
This hadith is sahih, like all the hadiths of this manuscript, and it appears in the separate manuscript under number 66. Bukhari related it, 123 (print) / 11:432 Fath, through the route of the manuscript, and likewise Muslim related it through its route, 53 (print) / 2:301-302 Bulaq. Its meaning has already come up repeatedly in the Musnad, at length and in brief, through several routes, including 7181, 7436, 7438, 7625, 7998, and 782. Ibn Hibban also related it in his Sahih, at length and in brief, 1:128, 129, 130, 133 in our edition, and we detailed its sourcing at the beginning.As for his saying, "There is no newborn who is born except upon this fitrah," in Bukhari's version through the route of the manuscript it reads, "There is no newborn except that he is born upon the fitrah." And the version of the separate manuscript reads, "Whoever is born, is born upon this fitrah." This agrees with Muslim's version through the route of the manuscript.