Megan Shepherd's The Secret Horses of Briar Hill
Oh lord, this is a weepy. Like sheer ugly crying through the last bunch of chapters. But what did I expect from the story of a little girl living in a tuberculosis clinic in England during WWII--a little girl who sees winged horses in the mirrors, and becomes determined to save one who is injured. Beautifully written and illustrated, a magical story--but seriously, bawl city. A/A-.
A review copy was provided by the publisher. This book is available now.