Zayd ibn Haritha al-Kalbi.

About Zayd ibn Haritha al-Kalbi

Zayd ibn Ḥāritha al-Kalbī, was an early Muslim, Sahabi and the former adopted son of the Islamic prophet, Muhammad. He is commonly regarded as the fourth person to have accepted Islam, after Muhammad's wife Khadija, Muhammad's cousin Ali, and Muhammad's close companion Abu Bakr. Zayd was a slave that Hakim ibn Hizam, Khadija's nephew, bought for her at a market in Ukaz. Zayd then became her and Muhammad’s adopted son and took his lineage. His lineage was later restored just before he had his second wife Zaynab bint Jahsh divorced and married to Muhammad. He later went on to marry into Muhammad's family.