The Two Princesses of Bamare by Gail Carson Levine
Princess Addie and Princess Meryl may be sisters, but they are as different as day and night. Princess Addie is shy and afraid of many things. Princess Meryl practices sword fighting and loves adventure. There is only thing that Princess Addie is not afraid of and Princess Meryl is: The Gray Death. Ironically, Meryl is the one to catch it. With only a few days before her sister dies, Addie decides to find the mythical cure. Only a dragon, a spector or a fairy would know. Will Addie find the cure in time to save her sister and the thousands of other people in the kingdom before it is too late?
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