The Prophet of Allah ﷺ said, "When a believer desires a child in Paradise, its conception, delivery, and growth to the desired age all occur in a single moment, just as he wishes."
حدثنا علي بن عبد الله حدثنا معاذ قال حدثني أبي عن عامر الأحول عن أبي الصديق
أن نبي الله ﷺ قال إذا أراد المؤمن الولد في الجنة كان حمله ووضعه وسنه في ساعة كما يشتهي
Its chain of transmission is hasan, due to Amir bin Abdul-Wahid Ahwal, whom Ahmad considered lenient while Abu Hatim and others deemed him reliable, and his hadith is found in Muslim. Muaz is the son of Hisham bin Abu Abdullah Dastawai, and he is trustworthy, while his father is firmly established. The hadith has already appeared at 11005.