Tracey Corderoy is a teacher and the author of Hubble Bubble, Granny Trouble. Her head is happily crammed with countless ideas and stories for children, which she began writing in 2006. She lives in Gloucestershire, England, with her family and a whole host of cute (but naughty) pets. Joe Berger, the illustrator of Hubble Bubble, Granny Trouble, is a children's author, illustrator, and cartoonist who also makes the occasional award-winning animated short film and title sequence. He is co-creator of the comic Berger & Wyse, which runs in the Guardian magazine each Saturday, and has illustrated numerous books for children and adults. Joe Berger lives in Bristol, England, with his wife, three daughters, two cats, and a small dog.