Muhammad bin Yahya bin Abi 'Umar محمد بن يحيى بن أبي عمر العدني · Chapters On Al-Qadar

"Every child is born upon the Millah, then his parents make him a Jew, a Christian, or an idolater." It was said: "O Messenger of Allah! What about those who die before that?" He said: "Allah knows best what they would have done." [Another chain) with similar in meaning, and he said: "Born upon the Fiirah."