Chapter on the Hajj of Children
Man Lā Yaḥḍuruh al-Faqīh|Volume 2|Book 3|Chapter 92
وَ رُوِيَ عَنْ أَيُّوبَ أَخِي أُدَيْمٍ قَالَ: سُئِلَ أَبُو عَبْدِ اَللَّهِ عَلَيْهِ اَلسَّلاَمُ مِنْ أَيْنَ يُجَرَّدُ اَلصِّبْيَانُ فَقَالَ «كَانَ أَبِي عَلَيْهِ اَلسَّلاَمُ يُجَرِّدُهُمْ مِنْ فَخٍّ ».
It was narrated from Ayyub, the brother of Udaym, who said: Abu Abdullah عليه السلام was asked: "From where are the children stripped (for Ihram)?" Imam عليه السلام said: "My father عليه السلام used to strip them at Fakh."
- Ṣaḥīḥ al-Faqīh, p. 157