Ursch is waaay bellow her in status, so it would be an easy thing to break their engagement if a more favourable were to come up, e.g. the engagement to a prince. We've now learned that the MC's mother even used to be a princess. However, that would make the 2nd prince the MC's cousin, which would be a whole other issue in itself (at least for us readers).
They could be non blood related or at least have very little blood relation even if her mother was a princess. Its possible for dukes from other lines to become king or a dukes son or daughter become part of the main royal family in the case of an heir passing away or even things such as a duke sending their son or daughter away or even adoption. Honorary titles could also be given to people.
Is she dumb? SHE IS ALREADY OFFICIALLY ENGAGED! SHE CAN'T GET ENGAGED TO THE PRINCE IF SHE IS ALREADY ENGAGED!
I understand after learning about the Prince's situation, since the Queen could force her to break her engagement. But before that? It makes no sense. Plus if these girls bought all those lies about Isabella and Ursch, this story about the mental condition of the royals might be fake as well.
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