Ruqayya married the third caliph `Uthman ibn `Affan and migrated with him to Ethiopia in 615 A.D., five years after the inception of the prophetic mission, accompanied by no more than nine others. That was the first of two such migrations. After coming back home, she died in Medina in 2 A.H. and was buried at Jannatul Baqee`. `Uthman then married her sister Ummu Kulthoom in Rabi` al-Awwal of the next (third) Hijri year. Ummu Kulthoom lived with her husband for about six years before dying in 9 A.H., leaving no children.
source: http://www.al-islam.org/masoom/bios/khadija.htm
We have already accepted the fact that a father can only give his daughter in marriage to a suitable match, one who is “pious” (Quran, 24:32), and who is not an evil-doer. Therefore, the fact that the Prophet (صلّى الله عليه وآله وسلّم) gave his daughters to Uthman (رضّى الله عنه) is proof enough of his good character. It is a refutation against all of the accusations and slander levied against Uthman (رضّى الله عنه) by the Shia propagandists. In fact, if the Shia say that Uthman (رضّى الله عنه) was an evil person, then they are declaring that the Prophet (صلّى الله عليه وآله وسلّم) violated the Quran and his own sayings by giving his daughter to an evil person. Indeed, what noble character Uthman (رضّى الله عنه) must have had that he got the honor of marrying not just one, but two of the Prophet’s daughters.
Abu Bakr (رضّى الله عنه)
Abu Bakr (رضّى الله عنه), the first Caliph, was so close and dear to the Prophet (صلّى الله عليه وآله وسلّم) that he gifted his daughter in marriage to the Prophet (صلّى الله عليه وآله وسلّم). Her name was Aisha (رضّى الله عنها), whom the Shia spread malicious slander against. Would the Prophet (صلّى الله عليه وآله وسلّم) really marry someone who was sinful and an evil-doer? This is accusing the Prophet (صلّى الله عليه وآله وسلّم) of sinning and violating the Quran as well as his own sayings. By marrying Abu Bakr’s daughter, the Prophet (صلّى الله عليه وآله وسلّم) showed his undying solidarity with Abu Bakr (رضّى الله عنه), who was his best friend and top lieutenant.
Umar bin Khattab (رضّى الله عنه)
Umar bin Khattab (رضّى الله عنه), the second Caliph, was also very close to the Prophet (صلّى الله عليه وآله وسلّم); he too gave his daughter, Hafsa (رضّى الله عنها), in marriage to the Prophet (صلّى الله عليه وآله وسلّم).
Ali ibn Abi Talib (رضّى الله عنه) gave his daughter, Umm Kulthoom bint Ali, in marriage to Umar (رضّى الله عنه). This very fact shatters the entire Shia paradigm, and the false idea that the Three Caliphs were enemies of Ali (رضّى الله عنه). The marriage of Umar (رضّى الله عنه) to Umm Kulthoom is documented in Al-Kafi, which is considered the most authentic book of Shia Hadith.
Conclusion
Ali (رضّى الله عنه) was on very good terms with the Three Caliphs, and they were Sahabah (Companions) one to another. Ali (رضّى الله عنه) served as vizier and top aid to all three Caliphs; therefore, the Shia historical accounts of bad blood between the House of Ali (رضّى الله عنه) and the Three Caliphs is false.
As can be seen, all of the Three Caliphs (which the Shia insult and call the “three fools”) were linked to Prophet Muhammad (صلّى الله عليه وآله وسلّم) through marriage, blood, or both. That is how close companions the Three Caliphs and the Prophet (صلّى الله عليه وآله وسلّم) were.
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