Li Hong
Also in 675, Li Hong the Crown Prince died suddenly—with traditional historians largely attributing his death to poisoning by Empress Wu, due to her anger that he tried to curb her power grab and had shown sympathy to his two older sisters born of Consort Xiao—Princesses Yiyang and Gao'an. Emperor Gaozong, in grief, posthumously honored Li Hong as an emperor, and he created Empress Wu's second son, Li Xian the Prince of Yong, crown prince.