Duan Yu is Duan Yanqing’s son.
Duan Yu, one of the male protagonists in Jin Yong's martial arts novel "The Eight Parts of the Dragon", is the eldest son of Duan Zhengchun, the southern king of Dali Kingdom (actually the son of Duan Yanqing and Dao Baifeng).
Duan Yanqing was originally the crown prince of Dali. He was persecuted by traitorous officials and escaped from the palace. Later, he was besieged by powerful enemies, his face was completely disfigured, his legs were disabled, and he could only communicate in ventriloquism. He originally wanted to seek death, but because of his romantic relationship with Dao Baifeng, he regained his faith. After recovering from his injuries, he took crazy revenge on those who had hunted him back then. Because of his cruel methods, he won the title of "Full of Evil" and became the first of the "Four Evil Men".