John Boyne 
Terrible Thing That Happened to Barnaby Brocket [EPUB ebook] 

There’s nothing unusual or different about the Brocket family — and they’re keen to keep it that way. But when Barnaby Brocket comes into the world, it’s clear he’s anything but ordinary. To his parents horror, Barnaby defies the laws of gravity — and floats. Soon, the Brockets decide enough is enough. The neighbours are starting to talk. They never asked for a weird, abnormal, floating child. Barnaby has to go . . .Betrayed and frightened, Barnaby floats into the path of a very special hot air balloon and so begins a magical journey around the world, with a cast of extraordinary new friends.