Tuesdays in the Castle by Jessica Day George

Celie is the youngest daughter of King and Queen Glower.  She and her family live in a most unusual castle.  It has a life of its own and changes from time to time, adding a room here, removing a hall there.  The royal family and staff are used to these changes, and even see them as the castle's way of taking care of the kingdom.  When the King and Queen are ambushed and thought dead, the castle goes into action to help Celie and her siblings retain power, and have hope that their parents are not really dead.  This is a cute fantasy full of imagination and clever twists on familiar themes.  The royal children are resourceful, but George manages to keep them child-like, instead of making them into little adults.  The story is engaging and exciting, but not violent and there are no objectionable elements.  It could be enjoyed by as old as middle school age children, but if there were a good reader who was in 1st or 2nd grade, they could enjoy it too. (p. 228)