Chapter on Virtues of Hajj
Man Lā Yaḥḍuruh al-Faqīh|Volume 2|Book 3|Chapter 2
وَ رُوِيَ: «أَنَّهُ قُتِلَ اَلْحُسَيْنُ بْنُ عَلِيِّ عَلَيْهِ اَلسَّلاَمُ وَ لِأَبِي جَعْفَرٍ عَلَيْهِ اَلسَّلاَمُ أَرْبَعُ سِنِينَ ».
It has been narrated: "Al-Husayn ibn Ali عليه السلام was martyred when Abu Ja'far عليه السلام was four years old."
- Ṣaḥīḥ al-Faqīh