By Jemima Laing
The books are illustrated by Dinosaur Cove artist Mike Spoor
There is a saying that you should never go back.
But that is not a philosophy that Devon children's writer Helen Greathead subscribes to.
The recent success of a series of fictional books about dinosaurs - Dinosaur Cove - got her thinking.
She figured that the four books she had written about dinosaurs eight years ago could find a new readership if they were updated and relaunched.
So she approached her original publishers - who agreed with her - and has now added 16 pages to each of the fact-filled books in the series which is now called Do You Know Dinos?
The books, illustrated by Dinosaur Cove artist Mike Spoor, are described as a "friendly, funny approach to the most exciting dinosaurs around".
And as Plymouth is the place the word dinosaur was first coined, it was fitting that Helen launched the books at a special event at the city's museum and art gallery in June.
The four books each look at the lives of a different dinosaur; the igaunadon, T Rex, stegosaurus and diplodocus.
The original books have been expanded with word searches, quizzes and activity pages.
"I didn't have a special interest in dinosaurs when I was a child," said Helen, who moved to Plymouth from London in 2000.
"But once I first wrote the books I found myself becoming more and more fascinated by them so coming back to the books has been really nice.
"What we know about dinosaurs is developing and changing all the time."
Helen - who had another series of books ,Tough Jobs, published in 2008 - has an impressive track record of being involved in the production of non-fiction books.
Helen Greathead first wrote the books eight years ago
She worked as an editor at Scholastic for 14 years, starting as desk editor and ending up as editorial director non-fiction.
She had already worked with author Terry Deary on a number of projects when he came up with the idea for what would become the hugely popular Horrible History books.
As well as commissioning the first Horrible Histories titles she was also instrumental in the Horrible Sciences, Horrible Geographies, The Knowledge series, Dead Famous and Top Tens.
So what does Helen think is the perennial attraction of dinosaurs for children?
"I think children always seem to be fascinated by monsters, it's the fear factor but with the relief they can't actually get you.
"And of course there is the gory element too."
Helen hopes the books will interest boys and girls alike and has enjoyed reading them with her own sons Bertie, 11, and Gideon, 8 - who wasn't even born the first time they were published.
"In fact Gideon was named after Gideon Mantell who I came across when I was researching the books the first time round," said Helen.
Mantell was a geologist and palaeontologist born in 1790 whose attempts to reconstruct the structure and life of the iguanodon began the scientific study of dinosaurs.
"He just seemed like a very nice person who came up against the establishment, so that's how our Gideon got his name."