Princess of Glass by Jessica Day George
Princess Poppy is now free of the curse that forced her and her eleven sisters to dance each night. Now, she is visiting the country of Breton to make friends with the royalty there. But a mysterious girl keeps showing up at the balls and casting spells on the people there. Poppy suspects that she is the maid Ellen, but no one knows where she is getting her gorgeous gowns from. Poppy is just the one to undo the curse that is on the poor girl, but can she do it before its too late?
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