Cao Zhi
Around 217, before Cao Cao left for the Hanzhong Campaign, Cao Zhi sang praises of his father while seeing him off and earned much favour from his father. Cao Pi, feeling uneasy that Cao Zhi had stolen the limelight, turned to Wu Zhi for advice. Wu Zhi instructed Cao Pi to cry while seeing his father off. Cao Pi did so and touched the hearts of many people, who felt that Cao Pi was much more sincere in expressing his emotions as compared to Cao Zhi. In another incident, Wu Zhi did not want to be seen as being too close to Cao Pi, so he sneaked into Cao Pi's residence by hiding in a silk hamper. When Yang Xiu, Cao Zhi's close friend and adviser, heard about it, he reported it to Cao Cao. Wu Zhi, knowing that Yang Xiu knew his trick, stopped sneaking into Cao Pi's residence and he instructed Cao Pi to refill the hamper with silk. When Cao Cao and Yang Xiu came to investigate, they did not find Wu Zhi hiding inside the hamper, so Cao Cao became very displeased with Yang Xiu.