Which episode directed by Swallow said that Emperor Qianlong was the murderer who hurt his father?

In the third episode of 17, everyone came to Cining Palace to have dinner with the Empress Dowager. Swallow is happy, Wei Zi and Er Kang are worried, Sang Ni is nervous, and Xiao Jian is calm and knowledgeable. The Queen Mother has decided to fulfill Xiao Jian and Sunny. Of course, she couldn't help asking about Xiao Jian's family. Xiao Jian was vague. At this time, the queen mother revealed that Fang Zhihang was questioned by the emperor. Xiao Jian was surprised. Swallow can't believe it. She only knew that her parents were killed, but she didn't expect her brother's father-killer to be her favorite emperor Ama.