Responses
Brother is in the academy...
I'd think that the attempts on his sister's life would warrant at least a visit to check on her well-being, regardless if he was in the academy or not. If he can't leave, surely being friends with the First Prince would allow some arrangement to be made to have someone trusted to check up on her.
Honestly I'm glad that our MC is stepping up to take charge of her own life and act independently. While she says she is simply keeping the dukedom safe until her brother returns, I think she by far deserves to be their leader.
His priorities clearly don't include her as someone on top of the list.
Maybe I'll be proven wrong later and I'll gladly take that but for now her brother is utterly absent and doesn't seem to put family as priority at all.