Query: What did Imam Ismail pass on to his son?
Context: They followed Isma'il ibn Jafar, elder brother of Musa al-Kadhim, as the rightful Imam after his father Ja'far al-Sadiq. The Ismailis believe that whether Imam Ismail did or did not die before Imam Ja'far, he had passed on the mantle of the imamate to his son Muḥammad ibn Ismail as the next imam. Thus, their line of imams is as follows (the years of their individual imamats during the Common Era are given in brackets):