Zainab, Muhammad’s oldest daughter, married a merchant cousin with wealth, Abu al ‘Aas ibn al Rabi’. When Muhammad started having revelations Zainab converted while her husband did not, causing strife. After Muhammad’s revelation that a monotheist must not marry a polytheist, Abu al ‘Aas sent Zainab to Medina to rejoin her family. Abu al ‘Aas ended up converting to Islam in 7 AH and went to Medina to be with Zainab until her death in 8 AH.
Ruqayyah, Muhammad’s second daughter, was first married to ‘Utbah, son of Abu Lahab, who was a Quraysh elite. This marriage was ended when Muhammad began having revelations that the Quraysh disagreed with. Ruqayyah then married ‘Uthman ibn ‘Affaan ibn Abul-‘Aas ibn ‘Abd Shams whom she stayed with until her death, which coincided with the Battle of Badr.
Umm Kulthum, Muhammad’s third daughter, originally married ‘Utaybah, the brother of ‘Utbah, sons of Abu Lahab. This marriage ended at the same time of Ruqayyah’s marriage to ‘Utbah, with the sisters being sent home together. Umm Kulthum remained unmarried until her sister Ruqayyah’s death in 3 AH. Umm Kulthum then married Ruqayyah’s widowed husband, ‘Uthman ibn ‘Affaan, earning him the title, Dhu al-Nurayn or “The Possessor of Two Lights”.
As we know, Fatima, Muhammad’s youngest daughter, married Muhammad’s cousin and childhood friend Ali.