Cressida Cowell, author of How to Train Your Dragon and number one bestseller The Wizards of Once, is coming to Barnes Children’s Literature Festival in May.

The author-illustrator of the favourite series lives just over the bridge at Hammersmith and can often be found writing in her shed.

“It’s nice to support something local and I often walk the dog down over the bridge through Barnes so it feels quite local,” she said.

“It’s always lovely to meet kids and families who are reading the books together, hopefully inspiring children. I’m very passionate to get them reading for pleasure

“These festivals are really so vital in getting kids excited about reading.

“There’s a huge amount of research that shows reading for pleasure helps them be successful in later life.

“It’s quite a difficult message to get across - we try to get to the parents as well as the kids involved.

“I might be encouraging parents to go into a book store and say, ‘what do you find has worked for kids?’ or ‘my children liked this, what is similar?’”

Cressida, a mother of three, said her own children have had ups and downs with reading, the important thing is not to nag them.

She said: “I have always been helping them and I haven’t been put off when they didn’t like reading, I have been able to say, ‘well maybe try something different, maybe try comics’.”

How to Train Your Dragon is also a wildly successful film franchise, courtesy of Dreamworks.

Dragons are generally friendlier in the animated films, more like trained dogs than the wily, self-serving beasts in Cressida’s illustrated books, but if children already know they love the world and characters it can be a gateway into reading, she said.

Cressida’s brand-new series, The Wizards of Once, has also been snapped up by Dreamworks despite only being published in hardback in September.

“It went straight to number one which is very exciting,” said Cressida, “children have really been enjoying them.”

“The Wizards of Once is my new series set in the Iron Ages when magic is really active.

“It’s about a girl hero who is a warrior but has a secret, and a boy who is a wizard and has no magic and will do anything to get it.”

The magic in her stories is partly inspired from her own childhood, “When I was a kid I really wanted to be magic, and I think everyone does,” she said.

However, these books weren’t magicked out the air.

“It’s not like I was instantly successful – my first book was written 20 years ago – but it’s been beyond my wildest dreams.

“I read English at university and I then went to art school for quite a long time and my first book I published I wrote in my MA.

“I entered a prize aimed at students and I won; that was my entry point and it evolved from there.”

Cressida Cowell’s new book The Wizards of Once is out now in hardback and will be published in paperback on May 3.

She will be at Barnes Literary Festival on Saturday May 12, find out more and book tickets at barneskidslitfest.org