The Dragonsitter (The Dragonsitter Series, 1) by Josh Lacey

The first book in a fresh and funny new chapter book series, told completely in emails, about a boy named Eddie and a naughty pet dragon!Dear Uncle Morton, You'd better got on a plane right now and come back here. Your dragon has eaten Jemima. Emily loved that rabbit! It had sounded so easy: Eddie just needed to look after Uncle Morton's unusual pet for a week while he went on vacation. But soon the fridge is empty, the curtains are blazing, and the mailman is fleeing down the front path. The Dragonsitter will have readers laughing out loud and begging for more adventures.