Julia Donaldson and Axel Scheffler are superstars in the world of children's literacy. 

Donaldson's fanciful, perfectly rhyming tales, paired with Scheffler's unmistakable illustrations make them a formidable force. 

The Gruffalo is one of the most successful book franchises in history, and they're returning to that familiar world with their newest creation: 'Gruffalo Granny'.  

It comes 27 years after the first book was published and 22 years after its sequel, 'The Gruffalo's Child', hit the shelves. 

Over twenty years is a fairly large gap, but Donaldson told Jack Tame she's hardly been twiddling her thumbs in the meantime.  

"I've written dozens of books in between," she said. 

"And it's quite hard to write a sequel ... you're not so free."  

The return to the deep dark wood also came as a surprise to Scheffler, who had no idea the book was in the works. 

"At least the Gruffalo and the Gruffalo's child knew that Granny was coming – I didn't know," he told Tame.  

"When I'm writing a story, I don't, if I tell someone I'm going to write a story about this, that and the other, and they go, "yeah, I'm not so sure", you know, then immediately I'll just clam up and I won't do it," Donaldson explained.  

"Plus, I've got to be happy myself. Sometimes I think I can write a story and then it doesn't work out so I have to keep it to myself and be happy before I show it to anyone." 

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