In the thirteenth year of King Ping of Zhou, Duke Zheng Wugong took control of the state of Zheng. Duchess Zheng Wu Jiang had difficulty giving birth to a child and named her Kou Sheng, who was very disgusted with Kou Sheng.

The second son, Duan, looks like a talent, his face is like powder, and his lips are painted with Zhu, which is deeply loved by Jiang. Jiang repeatedly praised his husband Zheng Wugong as the second son of Duan Zhixian, who should be established as the heir, but Wu Gong did not allow it, and still established Kou Sheng as the son.

Jiang was displeased. After the death of Duke Wu, Kou Sheng ascended the throne for Zheng Zhuanggong, Jiang and Duan Wuquan, and their hearts were unhappy.

One day, Jiang said to Zhuang Gong: "You inherited your father's throne and enjoyed hundreds of miles of land, but your brother has no place to live, so you should give him the title of the province." "Zhuang Gong did not obey his orders, and Feng his brother Duan lived in a place called Jing.

Duan entered the palace to bid farewell to his mother Jiang, and Jiang took the opportunity to provoke and said: "Your brother doesn't miss the feelings of his compatriots, treat you badly, today he named you the uncle of the capital, I pleaded again and again before agreeing, after you arrive in the capital, you can train soldiers, secretly prepare, as soon as you have the opportunity, I will be your internal response, let you replace the throne of Kou Sheng." Later, Gongshu Duan conspired with his mother Jiang to usurp power, but Zhuang Gong found out, and Gongshu Duan killed himself.

Zhuang Gong complained deeply about his mother, and swore: "It's not as good as Huangquan, and there is no way to see each other!" Seeing that Zhuang Gong placed his mother Jiang in Chengying, and swore that he would not see Huangquan or his mother, he said to others: "Although the mother has done something wrong, the son should not be so ruthless." I'm going to persuade him. Uncle Ying Kao caught a few birds, pretended to offer game, and came to see Zhuang Gong.

Zhuang Gong asked, "What kind of bird is this?" He replied, "Birds." This bird was fed by its mother when it was a child, and when it grows up, it will eat its mother, and it is an unfilial bird, so it is caught and eaten. Zhuang Gong listened and did not speak.

At this moment, a person sent steamed sheep, Zhuang Gong ordered someone to give Uncle Ying Kao a leg of mutton, Uncle Ying Kao picked up the meat and wrapped it in paper, and hid it in his sleeve, Zhuang Gong felt very strange, so he asked him what he was doing?

Uncle Ying Kao said: "I have an old mother at home, and because my mother has never eaten such a delicacy because of her poor family, I want to take it back to my mother to eat." Zhuang Gong sighed: "You are really a filial son!" He sighed.

Uncle Ying Kao asked, "Why are you sighing?" Zhuang Gong said: "You can do your filial piety to your mother, but I am a prince, but I am not as good as you." Uncle Ying Kao pretended not to know, and asked again, "Isn't Mrs. Jiang alive?" Why is it that the heart of the Son of Man has not been fulfilled? Zhuang Gong said: "I swore that I would not see my mother until Huangquan, and now it is too late to regret it." Uncle Ying Kao said, "I have a plan to reunite your mother and son." You can order someone to dig a tunnel, welcome Mrs. Jiang to live there, and you go there to see your mother, so that you can not violate your oath, and you can see mother and son, wouldn't it be the best of both worlds. Zhuang Gong was overjoyed and acted according to the plan.

Uncle Ying Kao used his wisdom to seriously figure out Zhuang Gong's inner activities, and adopted methods that ordinary people could not think of to reunite Zhuang Gong's mother and son, which solved a major problem for Zhuang Gong.