This really makes zero sense. What could the nobles possibly have to gain from not only letting their countries soldiers die, bleeding them of assets for future war, but losing prosperous land? I mean if they are jealous of the city then whatever, but a prosperous region in the kingdom helps them too due to the trade and farm land it creates. Unless the enemy nation is paying them VAST amounts of money or something, the loses from this would be devastating to the nation. That's not even mentioning the fact that the aunt seems to be a war hero, protecting the entire kingdom in that direction, and if every other lord knows it's these nobles trying to stop her how the fuck do they have ANY power whatsoever? You lose military might, resources, farmland, trade, completely destroy moral of the military in general, and the lose of a well known war hero would destroy the moral of the citizens as well, since now they would feel fear knowing she isn't guarding that area anymore. Like for real, the author is going to have to create a work rivaling The Illiad for any of what is happening to make sense.