Xi Zhengde was the Marquis of Yongning, father of Xi Ping, the Viscount of Yongning.1
When he was young, Xi Zhengde was once called the handsomest man in Jinping, and he was widely pursued by beautiful women.1
In Taiming 28, Xi Zhengde attended the Flower Viewing Festival at which the courtesan Jiangli was crowned Queen of Flowers, pressured into making an appearance by his peers. He was unimpressed by her and her competitors, idly munching melon seeds as he watched the performances, though he appreciated the refreshing break from gaudiness that Jiangli brought. He made to leave after she won, while her odd-looking musician made rounds of the audience, feeling that the beauty and skills of the "famous flowers" at the House of Overflowing Splendor were lacking and that, especially given the musician's appearance, they were rather disgracing themselves. He had no reason to stay once he'd fulfilled his social obligations.1
While leaving, as he went downstairs, he encountered the strange musician as she also tried to exit. Her height forced him to look her in the eye, despite not wanting to, and the Marquis was struck with the thought that, beneath the alarming makeup, she looked familiar. The musician, though she had been unbothered by the rowdy crowd, was visibly alarmed when she met the Xi Zhengde. She turned and sprinted away, leaving Xi Zhengde confused in her wake.1
Then, after his moment of shock, the Xi Zhengde had a realization. That strange musician was none other than his son, Xi Ping, in disguise.1
Xi Zhengde paled and clutched his chest as he realized this, alarming his gathered servants, and they crowded around to support him as he struggled to speak. After several failures to get the words out, Xi Zhengde finally took a deep breath and shouted for his servants to get him "that fiend"—his fleeing son. His servants thus set off running after Xi Ping.1