The Prophet ﷺ was asked, "Will you not marry the daughter of Hamza?"He replied, "She is the daughter of my brother through breastfeeding."Another narration adds, "What is forbidden through lineage is also forbidden through breastfeeding."
قيل للنبي ﷺ ألا تتزوج ابنة حمزة؟ قال: إنها ابنة أخي من الرضاعة. وزاد في رواية: وإنه يحرم من الرضاعة ما يحرم من النسب.
Bukhari related it in the Book of Marriage (5100), and Muslim in the Book of Breastfeeding (13:1447), both through the route of Shuba, from Qatada, from Jabir bin Zayd, from Ibn Abbas, who mentioned it. The wording is Bukhari's. The other version in Muslim comes through the route of Saeed bin Abu Aruba, from Qatada, with the same wording.