The Source of Eight Characters of Emperor Jiaqing
One reason is that Emperor Qianlong is a jade idiot.
Emperor Qianlong can be said to be one of the wise kings throughout the ages. His greatest hobby is collecting jade articles, so each of his sons will have a jade word next to him. Not only is his son so named, but his 800 poems handed down from generation to generation are all about jade, which proves how much he likes jade.
The second reason is that Jiaqing is the next successor
But he has a son whose name is not Yong. Why? Quite simply, that's because Jiaqing is the next heir, that is, the throne is his. Not surprisingly, you should know that in ancient times, it was disrespectful to the king not to clash with the emperor, so Qianlong would help him change his name in advance to avoid trouble in the future, and many people changed his name. For example, before Kangxi became emperor, his name was Michelle Ye, so no one could use these two words during his reign.
Also, even Xuanwu Gate has to be renamed, because it conflicts with the emperor's name, which is very bad for the emperor, so the ancients changed their name to Shenwumen.
The third reason is that Jiaqing changed its name.
But in Yongzheng, we still have to change, because Yongzheng is superior, and his name is Yin. What should we do? Yongzheng changed its name to Yun, but how did Jiaqing change it? The word forever is too common to be changed. Just change Jiaqing's name to one arm and one leg. No one can beat him. Everyone is very happy.
To sum up, as long as there is a prince with a different name from other brothers and sisters in the Qing Dynasty, it is basically certain that he is the next emperor. Their rules are rigid, so they are regular.