crispachu:
He is the crown prince of the previous dynasty, basically. The current dynasty's surname is Li, his is Xiao.
The thing is this wasn't revealed until around Episodes 7 or 8,. So I don't think it's something everyone knows. In the subtitles you're watching, is he also called the Crown Prince in the early episodes? If not, then I guess the subtitles I'm watching are incorrect cause also his first wife is called the crown princess
Just One More Episode:
Why is Xiao Wu Yi called the Crown Prince even though he's the second son of his family and not the emperor's son?
In Chinese, he was called "Shi Zi" meaning "The Heir" to the Jing'an Wang (translated as Prince Jing'an, but it is not Prince as in son of the Emperor, but a hereditary title like a Marquis). Therefore, his wife is called "Shi Zi Fei" (consort of the Heir). Usually, the first son will be the Heir, but because the eldest son was injured, thus he was deemed not fit to continue the title.
