Genealogy of Khadijah's daughters

Khadijah bint Khuwaylid, the first wife of the Islamic prophet Muhammad, had six children. Some Shia dispute whether all of the children were born in her marriage to Muhammad, or if three of the four daughters were born to a previous marriage.

The dispute extends to Zainab, Umm Kulthum and Ruqayyah. Shias believe Fatima was the only daughter of Khadija whereas Zainab, Ruqayya and Umm Kulthum were the daughters of Khadija's sister, Hala, who had strained relations with her husband and the two girls were brought up by Khadija after the death of Hala. It is notable that before the revelation of the Quran, Muhammad also had an adopted son, Zayd ibn Harithah, and Zayd's name was changed back from Zayd bin Muhammad to Zayd bin Harithah after the prohibition of conferring the non-biological father's name to the adopted.

This debate becomes significant and contentious since two of the children, Ruqayyah and Umm Kulthum were consecutively married to Uthman, one after the death of the other. Due to marrying two of the prophet's daughters, Uthman was called 'Dhul Nurayn' (Arabic: ذو النورين، He of the Two Lights).

The Quran refers to Muhammad's daughters as "banatika" (^{[Quran 33:59]}), the plural for "daughters".

There is another argument regarding the explanation of word "Banatika" that it does not refer to the immediate daughters but the daughters till the day of judgement. Means the Daughters of Daughter of Fatima.

This is the argument against the that the sisters of Fatimah were not the biological daughters of the prophet Muhammad as according to the universally accepted Islamic creed that the Qur'an will remain unaltered till it is lifted totally. Shia discard this logic based on a similar contradiction found in context of event of Mubahila for which Quranic verse 3:61 (^{[Quran 3:61]}) was revealed, though the verse calls for (in 'Arabic) at least 3 "sons", at least 3 "women", and at 3 least "selves" from each side in the Mubahila, only Imam Hasan ibn 'Ali and Imam Husain ibn 'Ali represented the "sons" of the Prophet, only Fatima al-Zahra represented the "women", and only Imam 'Ali ibn Abi Talib represented as the "self" or "soul" of the Prophet.

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