Lucy and Grace are sisters and friends they always argue who has got the biggest, it doesn't matter what, a cup or spoon or plate, thumb or ears, it doesn't really mater what. They just tease each other! Their mummy says. "Stop arguing. Do you know what would happen if your things just got bigger?" They say they don't know. And wonder what would happen! Suddenly there is a wallop and a flash then the Great Percy appears. Oh dear! He gives between them three wishes. What powers could the arguing sisters possible want!