Bismillah Walhamdulillah Was Salaatu Was Salaam ‘ala Rasulillah Narrated Ibn ‘Abbas (Radi-Allahu ‘anhu):
The Prophet (Sallallahu ‘Alaihi Wa Sallam) said about Hamza’s daughter, “I am not legally permitted to marry her, as foster relations are treated like blood relations (in marital affairs). She is the daughter of my foster brother.”
Bukhari Vol. 3 : No. 813