Yun Zhiyu: Became Gong Yuanzheng's Sister?

Nineteen years ago, on a snowy night, the wife of Zhenggong gave birth to her eldest daughter. Because the sun happened to shine on the land when the child was born, the owner of Zhenggong named his eldest daughter Gong Mingzheng. Time flew by, and two years later Zhenggong's wife gave birth to another son, who was later named Gong Yuanzheng. When Gong Mingzheng was nine years old and Gong Yuanzheng was seven years old, Wufeng disguised himself as someone from Perak Hall and entered the palace gate. Soon after, a group of assassins went around killing everyone in the palace gate. Later, Gong Mingzheng arrived in a hurry and rescued Mrs. Ling and Gong Langjiao. From then on, Gong Yuanzheng had a close friend and a brother beside him in the following decades...