Guest. A Changeling Tale

From the master of spookiness, Mary Downing Hahn. When malicious sprites called the Kinde Folke snatch Mollie's baby brother and replace him with a hideous changeling, Mollie travels through eerie, perilous lands to save him. When her adorable baby brother is replaced by an ugly, ill-tempered changeling, Mollie is determined to find the so-called Kinde Folke who took baby Thomas, return the changeling she calls Guest, and make them give Thomas back.
Natural and magical obstacles and her own reckless temperament make her journey arduous and full of dangers, and a plot rich in surprises and twists makes this book a must-read for Mary Downing Hahn's fans. Mary Downing Hahn is one of the most popular middle grade authors in the world, winner of numerous state awards as well as the Scott O'Dell Award for Historical Fiction (for Stepping on the Cracks) and the Mystery Writers of America Edgar Award (for Closed for the Season).