Fatimah bint Muhammad was the youngest daughter and, according to Shia Muslims, the only child of the Islamic prophet Muhammad and Khadijah who lived to adulthood, and therefore part of Muhammad's household. Her husband was Ali, the last of the Rightly Guided Caliphs, and her children include Hasan and Husayn, the second and third Shia Imams, respectively. She is the object of love and respect of Muslims, as she was the child closest to her father and supported him in his difficulties, was the supporter and loving caretaker of her own husband and children, and was the only child of Muhammad to have male children live beyond childhood, whose descendants are spread throughout the Islamic world and are known as Sayyids.