Why did Yiya kill her son in the Spring and Autumn Period?

Yiya, a native of Qi in the Spring and Autumn Period, was a famous cook at that time. He once "killed the son to serve the king" and participated in the coup. However, Yi Ya's plot to create trouble for Qi was a crime spurned by later generations, but it was a very common thing at that time, which was directly related to Qi Huangong's fainting in his later years. Yiya, as the embodiment of cooking, has been deeply integrated into the long-standing food culture of the Chinese nation. When he fled, the emperor was hungry. That guy slaughtered his son and cooked it for the emperor! Not a person. Yiya cooks. Yiya was a chef in charge of cooking in Qi Huangong during the Spring and Autumn Period. Duke Huan has lived in the palace for a long time and is tired of eating delicacies. I once said half jokingly, "I just haven't eaten steamed doll meat." In order to satisfy Huan Gong's wish, Yiya steamed her children and gave them to Heng Gong to eat. This flattery is perfect. Duke Huan thought he was loyal to himself, so he promoted and reused Yiya, and Yiya became a favorite. Finally, Yaya, Fang Kai and Vertical Carving jointly killed Qi Huangong. In order to gain Qi Huangong's appreciation, Yiya cooked for Qi Huangong with the meat of her young children, which made him appreciated and changed from a chef to a confidant around Qi Huangong.