He was sure that the Empress would be happy seeing their son, slowly coming out of his shell and going back to his past self. Coming back to the Evan, when he was a kid. Turning into the person whom Alexander know.
Now, all he had to do was to give Evan a good insight on all the royal affairs and hand him the empire. Evan was already capable to handle the kingdom. He was mature now and intelligent enough, he knew how to and when to talk to anyone. Alexander can almost see a successful Emperor in him, despite being so young.
The aristocrats and the imperial faction officials were also instantly agreed for announcing Evan as the crown prince, reasoning there were only princesses left except for a prince who is still playing in a sandbox with the other children. Indirectly telling, Evan is the oldest and smartest among all his children.
