sentences:  Contemporary sources attest that Nizar had sons.At least one of them, al-Husayn, fled with other members of the dynasty (including three of Nizar's brothers, Muhammad, Isma'il, and Tahir) from Egypt to the western Maghreb in 1095, where they formed a sort of opposition in exile to the new regime in Cairo.In 1132, following the highly irregular accession of al-Hafiz, al-Husayn tried to return to Egypt.