Someone asked the Prophet ﷺ, "Will you not marry the daughter of Hamza?"He replied, "She is the daughter of my brother through breastfeeding."
قيل للنبي ﷺ: ألا تتزوج ابنة حمزة؟ قال: إنها ابنة أخي من الرضاعة.
Bukhari narrated it in the Book of Marriage (5100), and Muslim in the Book of Breastfeeding (1447), both from the hadith of Qatada, from Jabir bin Zayd, from Ibn Abbas, who related it.Musab Zubayri said, Thuwaybah breastfed the Prophet ﷺ after she had breastfed Hamza, then she breastfed Abu Salama. Fath al-Bari (9/142).Thuwaybah, a diminutive form of the name, breastfed the Prophet ﷺ for a few days until Halima came to him. Thuwaybah had breastfed Hamza before him, and after him she breastfed Abu Salama bin Abdul-Asad. There is disagreement about whether she embraced Islam, and Ibn Manda mentioned her among the companions.Abu Naeem said, We do not know of anyone who mentioned her conversion to Islam besides him. What is mentioned in the biographies is that the Prophet ﷺ used to honor her. She used to visit him after he married Khadijah, and he would send her gifts from Madinah, until after the conquest of Khaybar, when she died, and her son Masruh also died. Fath al-Bari (9/145).