The renowned scholar of the Ahlus Sunnah, Ibn Abil Hadid in his commentary of Nahjul Balaghah relates that on the day of the Victory of Makkah which took place in the sixth year of the migration (Hijrah), a man named Hubar b. al-Aswad frightened Zaynab, the daughter of the Prophet(1) , who was seated in the camel litter, due to which the child in her womb was aborted.
Due to this act, the Prophet declared it lawful to shed the blood of Hubar. Ibn Abil Hadid further says that, “I related this incident to my teacher Abu Ja’far al-Naqib and he replied, ‘If the Prophet considered the shedding of the blood of Hubar b. al-Aswad to be lawful because he frightened Zaynab through which her child was miscarried, then it proves that if he would have been alive, he would have considered lawful shedding the blood of the one who had frightened Fatimah (sa) and due to which her child was miscarried.’ I asked him, ‘Then should I relate this through your authority that Fatimah (sa) was frightened and that her son, Muhsin (as) was miscarried?’ Abu Ja’far al-Naqib replied, ‘Do not narrate it’s accuracy nor it’s inaccuracy on my authority, while I am neutral regarding it and I refuse to speak out regarding it due to some reports present with me.’(2)
As-Sayyid Jazu’i composed the following beautiful couplets, “They made her swallow anger after her father, and how bitter it was, what she swallowed; they enraged her and in a way they enraged Allah the Lord of the Heavens; whose daughter was she and whose mother and whose wife, woe be to the ones who oppressed her and hurt her.”
(1) One of the numerous concocted stories of the non-Shi’a historians who allege that the Prophet had three daughters through Sayyidah Khadijah b. Khuwaylid (sa) apart from Sayyidah Fatimah al-Zahra (sa). The names of these daughters are stated as being Zaynab, Umme Kulthum and Ruqayyah, but in reality, they were the daughters of Hala b. Khuwaylid (wife of ‘Amr b. Hadam) and sister of Khadijah (sa), who after her death, were brought up by their aunt, Sayyidah Khadijah (sa) and Prophet Muhammad (sawa). The Shi’a scholars have put forward several proofs in refutation of this alleged claim which was raised simply to compete with Sayyidah Zahra’s (sa) personality and also because two of them were later married (consequently) to the caliph, ‘Uthman b. al-Affan (la).
(2) On one hand he agrees and opines that the crime had actually been committed, while on the other hand he hypocritically says that he is in doubt regarding this – such double standards!
Ref : Bayt al-ahzan fi masa’ib Sayyidat al-Niswan, Pg. 110