Two new characters have been created to celebrate 35 years of the Mr Men books.
The launch of Mr Birthday and Little Miss Birthday coincides with a special exhibition marking the anniversary.
The show, that opens at London's Animation Art Gallery on 5 April, features some of the best known Mr Men and Little Miss characters.
Creator Roger Hargreaves began making his first Mr Men character in 1971 until his death in 1988, when his son Adam began writing new stories.
Mr Tickle started it all off
Adam said: "My father was very successful in capturing basic human characteristics and turning them into something humorous."
He was the inspiration for the first character, Mr Tickle. When Adam was a child he asked his father what a tickle looked like.
The Mr Men books have sold over 100 million copies worldwide, making their creator the third best-selling author in British history.