Book the second. spoilers ahead for the first.
Emily gets to spend time between school sessions with Princess Alassa. Which is to say, join her on her formal journey to her Confirmation as heir (after which she will no longer need a regent), which entails her meeting a lot of princes who want to marry her.
Complications ensue. Like cockatrices.
Also a wizard who can turn himself into a whole murder of crows, merchants who are in a delicate position with the king, a temple, the attempts of various kingdoms to make conditions on the marriage, a spell on the royal family, and more.