Xiahou Xuan and Xiahou Hui; her personal name is unknown and she was referred to as the Lady of Deyang District (德陽鄉主). Cao Zhen had six sons: Cao Shuang, Cao Xi (曹羲), Cao Xun (曹訓), Cao Ze (曹則), Cao Yan (曹彥) and Cao Ai (曹皚). Among them, Cao Shuang inherited his father's peerage and marquisate as the Marquis of Shaoling (邵陵侯), while the other five also had their own marquis titles and marquisates. In 239, before Cao Rui died, he appointed Cao Shuang and Sima Yi as regents for his underage adopted son, Cao Fang, who succeeded him as the third emperor of Wei. In 249, Sima Yi staged a coup d'état against Cao Shuang and successfully seized power from him. After the coup d'état, Cao Shuang and his brothers were convicted of treason and executed along with their entire families. In Romance of the Three Kingdoms Cao Zhen appears as a character in the 14th-century historical novel Romance of the Three Kingdoms, which romanticises the historical figures and events before and during the Three Kingdoms period. He makes a late first appearance in Chapter 84 when he accompanies Cao Pi on a campaign against Eastern Wu. Cao Zhen starts to play a more important role from Chapter 91 onwards when the Shu regent Zhuge Liang launches the Northern Expeditions against Wei. His contributions in the series of battles against Shu are largely downplayed because the author, Luo Guanzhong, wanted to accentuate Sima Yi's resourcefulness and effectively portray him as Zhuge Liang's nemesis. Luo Guanzhong even attributed Cao Zhen's death to his failure to heed Sima Yi's forewarning of a Shu offensive. In Chapter 100, Sima Yi warns Cao Zhen that Shu forces will, within the next ten days, launch an attack on Mount Qi (祁山; the mountainous regions around present-day Li County, Gansu), a strategic location which would allow further incursions into the Wei heartland. After Cao Zhen refuses to believe Sima Yi, the two make a bet and each of them leads half of the Wei army to guard the valleys to the east and west of Mount Qi. Cao Zhen prepares for battle halfheartedly as he thinks that he is right. Seven days later, when his scouts report that a small number of Shu soldiers are approaching the valley, Cao Zhen sends his subordinate Qin Liang (秦良) to lead 5,000 men to survey the terrain. As Qin