The relationship between the two princes of Breviel was not always bad. When they were little, they actually had a harmonious relationship that others could envy.
The younger prince was like a shadow to the older prince. It wasn't a bad kind of shadow, but people often used the word to describe how the younger prince liked to follow the older prince everywhere like a shadow.
And the older prince didn't mind even if the younger kept following him like he was a tail or something. Contrary to that, the little Crown Prince always liked to have his brother around him.
However, everyone knew that the shadow would only stay with its original body under the sun or maybe under the lights. If the body chose to remain in darkness, then the shadow couldn't even appear.