If Birds Fly Back

Linny has been living life in black and white since her sister Grace ran away, and she's scared that Grace might never come back.
When Linny witnesses the return to Miami of a cult movie star long presumed dead, she is certain it's a sign. Surely Álvaro Herrera, of all people, can tell her why people come back - and how to bring her sister home?
Sebastian has come to Miami seeking his father, a man whose name he's only just learned. An aspiring astrophysicist, he can tell Linny how many galaxies there are, how much plutonium weighs and how likely she is to be struck by a meteorite. But none of the theories he knows are enough to answer his own questions about why his father abandoned him, and why it left him in pieces.
As Sebastian and Linny converge around the mystery of Álvaro's disappearance - and return - their planets start to collide. Linny's life is about to become technicolor, but finding the answers to her questions might mean losing everything that matters.