I can't say enough good things about Far From the Tree by Robin Benway. This book was the 2017 National Book Award winner for Young People's Literature, an award given through the National Book Foundation in November of each year. In this complex story about family dynamics, adoption, love, and more, teenagers Grace, Maya, and Joaquin discover they are biological siblings. As they get to know each other, the reader watches their individual lives unfold and their definitions of family expand. I completely agree with the NBA judges' citation. This book is "uplifting and big-hearted".
This year's Young People's Literature longlist also includes authors who've visited Kalamazoo Public Library in the past, like Mitali Perkins just recently in 2017, and Jason Reynolds in 2015 and 2016. The whole list is here.
The National Book Award list is one of my favorite "Best of" lists each year. I mean, other than the KPL "Best of" lists. The entire list is impressive and the winners are chosen by a committee of book industry experts and established authors who work all year long, reading and critiquing books to find the best of the best in each category. You might recognize some big Young Adult author names from this list of judges: Meg Medina (Chair), Brendan Kiely, Kekla Magoon, Alex Sanchez.