In the event of 'Āshūrā which took place during the month of Muḥarram in 61 AH, three noble Imāms were present.Imām Ḥusayn (as) who headed this revolution and was martyred in Karbalā. Imām Sajjād (as), [who] for reasons could not participate in the battle, and in accordance to God's will, he remained alive to take on the Imāmat of the Shī'ahs [after his fathers martyrdom]. Imām Bāqir (as) was also present at the event of Karbalā.
The 'Āshūrā, uprising which took place during the month of Muḥarram in the year 61AH, is one of the most important and influential events in the history of Islām.
Three honorable Imāms were present at this eventImām Ḥusayn (as) who headed this revolution and was martyred in Karbalā. Imām Sajjād (as), [who] for reasons could not participate in the battle, and in accordance with God's will, he remained alive to take on the Imāmat of the Shī'ahs [after his fathers martyrdom]. Imām Bāqir (as) who was four years old at the time.
Here we will examine the evidence regarding Imām Sajjād (as) and Imām Bāqir (as) being present at Karbalā.The presence of Imām Sajjād (as) in Karbalā is a matter that all historians unanimously agree upon and none have disputed. Imām Sajjād (as) played a vital role in not allowing the blood of the martyrs of Karbalā go to waste.
One of the proofs for his presence in Karbalā is the historical account of his speech in Yazīds palace.
Also one narrator says, "In the year 61AH I entered Kūfah, this was concurrent with the time that 'Ālī ibn Ḥusayn (Imām Sajjād) (as) and the womenfolk of his family were returning from their (heartbreaking) trip to Karbalā."
Imām Sajjād (as) says about his presence on the day of 'Āshūrā, "We exited with Imām Ḥusayn (as) (from Madīnah)… on Saturday the 10th of Muharram 61AH, after the Ẓuhr prayers he was unjustly martyred."
The presence of Imām Bāqir (as) is also something that historians agree upon since there are many reports that state he was born before 61AH.
"Imām Bāqir (as) was born in 57AH in Madīnah."
Similarly, when a person asked Imām Bāqir (as), "Were you there in the era of Imām Ḥusayn (as)?" the Imām replied, "Yes".
Imām Bāqir (as) says in respect to his presence at Karbalā, "My Grandfather Imām Ḥusayn (as) was killed when I was four years old, and I still remember his being killed."
In accordance to this selection of accounts, there is no objection (or obstacle in proving) that Imām Bāqir (as) was present in Karbalā, and naturally since his eminence was quite young at the time he lived and travelled with his family. Also since he was very young at the time, the books of history have mentioned very little information about his presence in Karbalā.
 The Moral Lifestyle of Imam Sajjad (as), 2303 (site: 2411).
 Shaykh Mufid, Al-Amaali, p. 321, Shaykh Mufid World Congress Press, Qum, 1413 AH.
 Majlisi, Muhammad Baqir, Bihar al-Anwaar, vol. 45, p. 90, Al-Wafa' Institute, Beirut, 1404 AH.
 Bihar al-Anwar, vol. 46, p. 212.
 Kulayni, Al-Kāfī, vol. 4, p. 223, Daar al-Kutub al-Islamiyyah, Tehran, 1365 (solar).
 Ahmad ibn Abi Ya'qub, Taarikh Ya'qubi, vol. 2, p. 320, Beirut, Daar Saadir, no date of publication.