Shiism is a Persian corruption of Islam. It has nothing to do with Muhammad's household.
Indeed, 99% of Shiites beliefs and rituals evolved after Islam was completed and perfected..
The Prophet Muhammad never taught Taqiya, Mutaa, Tatbeer, Bada, Imamism, the alleged Tahreef of the Quran, deification of Fatema, pagan rituals on Ashura, Aghakhanism, Khoms, chest-beating, buiding of Husseiniyees, etc. All of this is innovation in religion. It has nothing to do with Islam.