Ewing, Amy. Cerulean #. 2

"Sequel to The Cerulean."

Sera has finally recognized the true power of her Cerulean blood. But in order to return home, she'll need help from Agnes, Leo, and their grandmother, the only person with knowledge about the mysterious island of Braxos, where the Cerulean tether is anchored. Though the journey will be treacherous, Sera will risk anything to see her City again. Meanwhile, the High Priestess's power has reached new heights in the City Above the Sky. And when Leela begins having visions of Sera, alive, she knows she's the key to saving the City. But to bring Sera home, Leela must channel the strength, courage, and curiosity that once got her friend exiled. With the help of friends, family, and Cerulean magic, Leela and Sera could soon return to their normal lives. But when that time comes, will Leela be able to serve her City as blindly as she once did? And will Sera be able to leave everything and everyone she's grown to love on the planet behind?