Narrated from Sayyiduna Ali (may Allah be pleased with him), he says: I said, "O Messenger of Allah! Shall I not tell you about a girl who is the most beautiful among the Quraysh?" The Prophet (peace and blessings be upon him) said, "Who is she?" I said, "The daughter of Sayyiduna Hamza." The Prophet (peace and blessings be upon him) said, "Do you not know that she is the daughter of my foster brother? Indeed, Allah has made unlawful by reason of suckling (fosterage) those relationships which are unlawful by reason of lineage."