Books like Wednesdays in the Tower

A castle that is constantly rearranging itself, and a young royal family sworn to protect it... Celie, Rolf, and their beloved Castle Glower are back in this exciting sequel.Strange things are afoot in Castle Glower: new rooms, corridors, and even stables keep arriving, even when they aren't needed. Celie's brother Bran, the new Royal Wizard, has his hands full cataloguing an entire storeroom full of exotic and highly dangerous weapons, while Celie has her hands full . . . raising the creature that hatches from a giant egg she finds! Will they be able to find out what's making the Castle behave this way in time?