Bertie has shockingly dirty habits, from nose-picking to eating sweets off the ground. Whenever he does anything dirty, his family shout, No, Bertie! That's dirty, Bertie! Will Bertie ever kick his horrible habits?
David Roberts was born in Liverpool and did a Fashion Design degree at Manchester Polytechnic. On leaving college he travelled to Hong Kong and worked as a fashion illustrator. On returning to England he worked as a couture milliner while doing regular illustration work for magazines. He is now a full-time illustrator. Keith Chapman always dreamed of being an artist, accepting his first commission - a drawing of a camel for his maths teacher in exchange for a box of Maltesers - at the age of seven. He studied Graphics at Yarmouth Art College and went on to work for the Jim Henson Company. In 1995 Keith created Bob the Builder, now a billion dollar brand and in 2001 he formed his own production company, Chapman Entertainment.