Just a couple of things about the Otherworld. It was not one of the 12 original kingdoms. If you have started to read the book in chapter Five, The Otherworld, the reader gets an intro to that part of Medelia. The unique feature of the Otherworld is the Ceiling Sky that separates Crater Lake and Hollow Cave. "The bottom of one is the top of the other."
It's the Ceiling Sky that helps to keep the "Others" safe from the perils of Medelia after the betrayal. Just the idea that the Others might break open the Ceiling Sky and thus cause a flood that might engulf most of Medelia keeps the region safe. There were a number of stories and legends as to how the Ceiling Sky came to be and what keeps the membrane / fabric in place. Most of the Others have purple hair. Now, it's important to mention that hair color in Medelia is something that can not be changed. No dye or coloring can change the hair color one is born with. In the Chronicles, those born with purple hair have been scapegoated for most of the troubles in the world.
So the challenge I faced (how delightful it was) to talk about race in a way that had not been written about !!!! not sure if I succeeded but creating characters with purple hair that can not changed was my way of doing this.....if the series takes off, I am hoping that "kids"....:) will be able to discuss the subject of race and racial prejudice in a way that won't offend anyone and still be able to "talk about it all..." will see I can succeed in this delicate area.... (as far as I know, no one has ever been born with purple hair) :)
Now of course, there is a foreshadowing of a "great flood"....we'll have to see if that really happens :)