Yellow Emperor. Cao Pi was very pleased. Once, Cao Pi wanted to send Lady Ren (), one of his concubines who fell out favour with him, back to her family – which meant that he was divorcing her. When Lady Zhen heard about it, she told her husband, "Lady Ren comes from a reputable clan. I can't match her in terms of moral character and looks. Why do you want to send her away?" Cao Pi replied, "She is unruly, impulsive and disobedient. She has made me angry many times before. I'm sending her away." Lady Zhen wept and pleaded with her husband, "Everyone knows that you love and adore me, and they'll think that you're sending Lady Ren away because of me. I fear that I'll be ridiculed and accused of abusing your favour towards me. Please consider your decision again carefully." Cao Pi ignored her and sent Lady Ren away. In 211, Cao Cao embarked on a campaign to attack a coalition of northwestern warlords led by Ma Chao and Han Sui, leading to the Battle of Tong Pass and the subsequent battles. Cao Cao's wife Lady Bian followed her husband and stayed at Meng Ford (孟津; present-day Mengjin County, Henan), while Cao Pi remained in Ye (in present-day Handan, Hebei). Lady Bian fell ill during that time. Lady Zhen became worried when she heard about it and she cried day and night. She constantly sent messengers to inquire her mother-in-law's condition, but refused to believe them when they reported that Lady Bian was getting better, and she became filled with greater anxiety. Lady Bian later wrote a letter to her, telling her that she had fully recovered, and only then did Lady Zhen's worries disappear. About a year later, when Lady Bian returned to Ye, Lady Zhen rushed to see her mother-in-law and displayed mixed expressions of sadness and joy. Those who were present were all deeply moved by the scene before them. Lady Bian assured Lady Zhen that her illness was not serious and praised her for her filial piety. In 216, Cao Cao launched another campaign to attack the southeastern warlord Sun Quan, leading to the Battle of Ruxu in 217. Lady Bian, Cao Pi, Cao Rui and Princess Dongxiang all followed Cao Cao on the campaign, but Lady Zhen remained in Ye because she was sick. When Cao Pi and Lady Zhen's children returned