The blood of Siren.

It would have been best if Duke Akris has said that the world wasn't round because it would have been much more believable than this—— Alexis was the child born from the affairs of the Emperor and Madam Regina? But she has never heard about the existence of the prince before this, in fact, there was no mention of the birth of a third prince. If there was, then her father would have told her about it, so how was it possible that a prince was born and no one knew about it?

Even the Duke whose birth wasn't celebrated in the empire

She picked the paper up and after much hesitancy wrote —- I have never heard about the birth of a third prince before tonight.