After Qianlong, Emperor Jiaqing inherited the throne, namely Aixinjueluo Yongyan. Which son was he?

Emperor Jiaqing - Yong Yan

Yong Yan, the fifteenth son of the emperor

Qianlong had three crown princes. The first crown prince was the second son Yonglian, born to the Queen Fucha family. Qianlong believed that "Yonglian was born to the Queen, my legitimate son, smart, noble, and extraordinary." After Qianlong came to the throne, he personally wrote a secret decree to establish Yonglian as the crown prince, which was hidden behind the "Upright and Bright" plaque in Qianqing Palace. However, Yonglian died when he was 9 years old. The second crown prince is Yong Cong. After Yong Lian died of illness, Qianlong named Yong Cong, the ninth son of the emperor, but he died early due to pox when he was 2 years old. The third crown prince was Yong Yan, the fifteenth son of the emperor, who later became Emperor Jiaqing. Jiaqing's name was originally Yongyan, why was "Yong" changed to "Yong"? Here is a brief introduction to the names of the emperors of the Qing Dynasty. There are no taboo rules for the names of Emperor Taizu Nurhaci of the Qing Dynasty, Emperor Taizong Huang Taiji of the Qing Dynasty, and Emperor Fulin of the Qing Dynasty. They only have yellow stickers on the royal names that appear in certain documents such as "Records" and "Jade Certificates" (that is, stamping the names with yellow stickers). . The taboo about the names of Qing emperors started with Emperor Kangxi. The general situation is: the character "Xuan" in Kangxi's name Xuan Ye was missing the last stroke when it was taboo; the character "Yin" in Yongzheng's name Yinzhen was missing the last stroke when it was taboo, and he ordered his brother to change the character "Yin" to "Yun" "" character; the character "红" in Qianlong's name Hongli (written as "Hongli" at that time) was missing the last stroke when avoiding taboo. The word "li" was changed to the word "暦". When it came to Yongyan in Jiaqing, Qianlong considered the taboo of the monarch's name. The character "Yong" was a commonly used character and it was inconvenient to avoid taboos. He ordered the character "Yong" in Yongyan to be changed to the uncommon character "陙". After Yongyan succeeded to the throne, he was renamed "Yongyan". The names of the emperors of the Qing Dynasty changed the characters for seniority to special characters, starting from Jiaqing.