Sayyiduna Ibn Abbas (may Allah be pleased with them both) narrates that a person once submitted in the court of the Messenger of Allah (peace and blessings be upon him): "O Messenger of Allah (peace and blessings be upon him)! Why do you not marry the daughter of Sayyiduna Hamza (may Allah be pleased with him)?" The Prophet (peace and blessings be upon him) replied: "She is my foster niece." (In fact, the Prophet (peace and blessings be upon him) and Sayyiduna Amir Hamza (may Allah be pleased with him) were foster brothers as well as uncle and nephew.)