Sarah Oliver is a writer from Widnes in Cheshire. She was the author of Miley Cyrus A-Z and is the most prolific One Direction biographer. She also wrote the Rihanna biography - The Only Girl In The World and appeared in the documentary, One Direction - All For One. Sarah has been a Smiler from the beginning and loves chatting to Miley's biggest fans on Twitter. Why not follow Sarah - @SarahOliverAtoZ - and join the conversation!