It is narrated from Sayyiduna Ali (may Allah be pleased with him) that once I said to the Prophet (peace and blessings be upon him): O Messenger of Allah! Shall I not tell you about one of the most beautiful virgins of the Quraysh? The Prophet (peace and blessings be upon him) asked: "Who is she?" I said: The daughter of Sayyiduna Hamza (may Allah be pleased with him). He said: "Do you not know that she is my foster niece, and Allah Almighty has made unlawful by reason of suckling all those relationships which are made unlawful by reason of lineage."