Twenty years ago Julia Donaldson and Axel Scheffler published their first picture book together A Squash and a Squeeze and have since written over twenty books together, including the timeless The Gruffalo. To mark this special anniversary Axel Scheffler has created a special piece of 20th anniversary artwork including characters from A Squash and a Squeeze and he and Macmillan Children's Books have donated this original artwork to Farms For City Children, who are running a 'digital raffle' to raise money to support the work of the charity.