Responses
Inferiority complex and laziness. It's easy to pass off her achievements as their own and she's the daughter of his brother that his beloved wife was getting busy with. King had weaker powers than his brother too so he resents her existence. Why would he want to give power back the child of the brother he hated instead of one of his own while using the FL?
Lol. Berry kingdom is so weird. Why would she treated MC like that? Even if she has different father, the king can just adopt her. MC is smart and she has great magic power. She basically the one who run the country.