Sahih Muslim #6759 · The Book of Destiny

Sahih MuslimAbu Huraira reported Allah's Messenger
Sahih Muslim · Book 46 · The Book of Destiny
Sahih Muslim · كتاب 46 · كتاب القدر
No babe is born but upon Fitra. It is his parents who make him a Jew or a Christian or a Polytheist. A person said: Allah's Messenger, what is your opinion if they were to die before that (before reaching the age of adolescence when they can distinguish between right and wrong)? He said: It is Allah alone Who knows what they would be doing.
حَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا جَرِيرٌ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏
"‏ مَا مِنْ مَوْلُودٍ إِلاَّ يُلِدَ عَلَى الْفِطْرَةِ فَأَبَوَاهُ يُهَوِّدَانِهِ وَيُنَصِّرَانِهِ وَيُشَرِّكَانِهِ ‏"‏ ‏.‏ فَقَالَ رَجُلٌ يَا رَسُولَ اللَّهِ أَرَأَيْتَ لَوْ مَاتَ قَبْلَ ذَلِكَ قَالَ ‏"‏ اللَّهُ أَعْلَمُ بِمَا كَانُوا عَامِلِينَ ‏"‏ ‏.‏
Reference : Sahih Muslim 6759In-book reference : Book 46, Hadith 37