Beaky Malone, Worlds Greatest Liar (Becky Malone, Bk. 1)

Dylan Malone, aka Beaky, has a habit for telling porkies - every time he opens his mouth, out pops a whopper...But then his long-suffering sister shoves him into the truth-telling machine at Madame Shirley's Marvellous Emporium of Peculiarities. Now Beaky can't tell a lie - not even a teeny-weeny one - and a truth-telling Beaky is even worse...