Cai Taizu's word dejue! Cai Zhou was born in Xiangyang (now Laoying, southeast of Xiangcheng, Xiangfan City). Xiangyang nationality at the end of han dynasty. His father Cai is sarcastic! Zhuge Liang's father-in-law, Huang Biao and Liu Biao, are sons-in-law of Cai Biao, whose sons are subordinates of Cai Mao and Liu Biao. In other words, Liu Biao is Zhuge Liang's brother-in-law, and Cai Mao is Zhuge Liang's brother-in-law. It's too complicated ~ I have two younger brothers named Cai Zhong and Cai He! In "Battle of Red Cliffs" in The Romance of the Three Kingdoms, Jiang Gan stole the forged surrender of Zhou Yu from Cai Mao and Zhang Yun, which led to Cao Cao's beheading!