Lily and Dunkin by Donna Gephart

This book combines and tackles and interesting combination of issues.  Dunkin is bipolar, like one of the author's sons, and his story also includes another issue.  Lily, born as Tim, is transgender and wishes to start hormone therapy, but her dad is not on board with that.  The book follows the two of them along with Lily's best friend, Dare and her new friend, Amy.  This book addresses a lot of timely issues in the story.