Laughter is such an integral part of children’s books that a special prize for funny ones might seem odd. Who doesn’t laugh at The Cat in the Hat, the misadventures of Just William and the scatalogical rudeness of Roald Dahl’s Revolting Rhymes?

Yet since children’s literature moved into crossover fiction, it has grown steadily darker. There has always been darkness, of course: few things could be grimmer than Grimm, or more frightening than Peter Rabbit’s struggle not to be put into a pie.

Children’s classics address big philosophical questions without turning a hair. But the other side of fairytales, on which all good books draw, is comedy. Sausages stuck to noses, being stuck on the lavatory and, of course snot, farts and private parts are what children have always found hilarious. Writing comedy for children, however, needs perfect timing. Paddington Bear and Horrid Henry, below, make young readers laugh because the protagonists do things that even a child knows will go wrong, resulting in dirt, breakage and rumpus.

Children need comedy as a defence against injustice, and the best authors have always poked fun at snobs, bores, whiners and creeps. Sex is still taboo, as is racism. After generations of Billy Bunter and Dahl’s Augustus Gloop, “the big, fat, greedy nincompoop”, authors are worried about mocking overweight children; even Dudley Dursely got a makeover in the last Harry Potter book.

Since children’s books have become money-spinners, humour has been less valued. No comic children’s novel has ever won the Carnegie Medal. Yet they need comedy now, just as they did in the Depression. Laughter, as Nabokov said, is the best pesticide. This is why the Dahl prize is so important.

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