I feel like the mother just hates her too much to just keep having her around. They can just say after all the brother „accomplished“ he wants to step back and focus on being the heir yk. No matter how convenient Radis was for the mom she didn’t want to do anything good for the Child she hates so much idk
But they crave money, and "the brother" is loyal to the empire, if he is assigned, he will go to the front line. Every household sends their heirs as a sign of loyalty.
Having Radis pretend to be her brother was pretty short-sighted of the mother to begin with. By the time Radis was dying the mother's biggest worry was getting caught so it probably seemed like the most convenient time to cut her losses. Especially when she'd just been handed that massive mana stone.
This story isn’t that good, mostly all over the place. And why would the mother let her die? I mean didn't the mother want her to pretend to be the brother? They act quite off too. Also because of the first chapter, i thought the black haired guy was someone bad, making our fl seduce the white haired guy, so then he can make her betray him and get him killedi am dropping this.