This movie is about what you'd expect for a "royal" movie where the prince tries to hide his identity. In this case, he is a supremely talented piano player who is shamed into subbing as the pianist for a children's choir performance and rehearsals after he smashes pastry samples DeeDee is carrying. Somehow, there are several days of the typical Christmas activities tied into it for the kids. Meanwhile, his mom and dad, the King and Queen, are pushing him to marry a Duchess. If you sit down and write a plot outline for the rest of the movie before watching it you are bound to be almost perfectly correct.
At one point, DeeDee reveals she was once in the armed services. This could have been an interesting subplot, but it barely comes up again.
The story is thin and recycled. The relationship is OK, but nothing outstanding. There's a small bit about their separate ornaments which again could have been expanded more.
This would probably be a decent movie if you had never seen a Christmas romance before, at least not a "royal" one.