J. G. Ballard, an unexpected fan of A. A. Milne’s bear, said that Winnie-the-Pooh was one of the three most successful characters in 20th-century fiction, “taking his place beside Peter Pan and James Bond, juvenile heroes who made the sensible decision never to grow up”.

Peter Pan had a second life in Geraldine McCaughrean’s admirable sequel, Peter Pan in Scarlet; Sebastian Faulks is not alone in continuing Bond’s fictional life. And now after 80 years, the Trustees of Pooh Properties have authorised a sequel to the Pooh stories.

Should we be surprised? Is it just “a commercial scam”? An attempt to bring a fading product back into the limelight? Surely not, for Winnie-the-Pooh has never gone away. The publisher tells us that it is “currently available in 50 languages around the world”. There were apparently only half that number when Ballard was writing in 1992. He went on to say (in spite of Dorothy Parker’s nasty review of The House at Pooh Corner) that he had “never known anyone who remembered Pooh with less than total affection”. The books have always sold in vast quantities: 2.25 million in 18 months, for instance, when the paperbacks first appeared in 1965.

Rumours of Return to Hundred Acre Wood (written by David Benedictus and illustrated in E. H. Shepard’s style by Mark Burgess) have aroused dismay and even anguish among purists and casual admirers alike. But Pooh’s appeal has been exploited from the very beginning. Early on, Milne and Shepard both happily authorised all sorts of spin-offs: soft toys, board games, bookends, writing paper, children’s china. There have been masses of books: birthday books, a workout book,The Pooh Book of Quotations and so on, quite apart from the wonderful essays (which make serious literary criticism impossible) by Frederick Crews in The Pooh Perplex and Postmodern Pooh, and the curiosities The Tao of Pooh and The Te of Piglet.

The new book is a different matter. Milne himself had made it clear that there would never be a sequel. He was concerned for his son: “I feel that the legal Christopher Robin has already had more publicity that I want for him . . . I do not want C. R. Milne ever to wish that his names were Charles Robert.” He would inevitably wish exactly that; his father’s decision could not prevent him becoming one of the five most famous children in the world. Christopher Milne died in 1996, but Milne’s second reason for stopping is still relevant. He didn’t think he could write another Pooh book “better than the one before”.

Benedictus may dislike the word “pastiche”, but this surely exactly describes his book. It is a “professed imitation” of another, as the dictionary has it. On the internet we can read that Benedictus “tried to enter Milne’s mind, to find his voice”, that when he’d read “everything by and about him”, “I felt I could become him ... What I had to do was imagine myself to be Milne.” The lines were to seem “as if they had just emerged from the pen of A. A. Milne himself”. A tall order. As Milne’s biographer, I think I can hear Milne’s voice in my head, and there are times when Benedictus does find that voice. Years ago he wrote two stories on spec and sent them to the trustees; eight years later the trustees gave him this extraordinary challenge, holding out to him the hope that his book would also be a worldwide bestseller.

Benedictus imagines Milne as “a sort of old uncle sitting in the background, either smiling or frowning at my efforts”. I suspect that Milne would be frowning. He would have thought this a foolish enterprise, however lucrative. I can’t help sympathising with Benedictus — for anyone who sells in hundreds a year, rather than hundreds of thousands, the contract would be impossible to resist. As he says: “I won’t have destroyed the originals in any way at all.”

The new book starts well, with Burgess’s lovely coloured endpapers providing a more accurate map than Shepard did in his delightful black and white originals to the first edition. Burgess, I am sure, knows Ashdown Forest better than Shepard, who went there only once. There must have been huge discussion about the title of the new book. In the originals, most of the action takes place in the Forest, not Hundred Acre Wood. Pooh himself “lived in a forest all by himself under the name of Sanders”. Now, Piglet has moved in with him, having given up his own tree to Owl.

I have always maintained that writers are more important than illustrators. The original books could have succeeded with another artist but not, of course, without Milne. With the new book, Burgess seems indispensable. No one else, surely, could have done so well. The toys and the animals look exactly the same, or as nearly the same as Burgess can make them. Even Lottie the Otter, the one new character, looks as if Shepard might have drawn her. Burgess’s skill in drawing in Shepard’s style is remarkable.

Lottie the otter played a prominent part in the advance publicity for the new book. “After 80 years, Pooh has a new friend,” as the Daily Mail put it. But Lottie is not very significant. She’s a bit player, fitting into the Forest without fuss. The memorable characters remain Milne’s. Return to the Hundred Acre Wood may well please children, who don’t care when or why a book was written, or who wrote it. If at times the stories seem not as good as we would like them to be, we have to admire and envy Benedictus for the way in which he tackles an impossible challenge, trying so hard to get it right. Pooh and Piglet had offered to help him to get it right, and it was Eeyore, of course, who added, “Not that you are likely to. Nobody ever does.”

Return to the Hundred Acre Wood by David Benedictus, illustrated by Mark Burgess (Egmont, £12.99 £10.39; 216pp)

Ann Thwaite’s A. A. Milne: His Life won the Whitbread Biography Prize in 1990. It is now available in paperback from Tempus/The History Press

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