Generations of children the world over have long adored AA Milne's tales of Winnie-the-Pooh and his motley band of pals, Tigger, Piglet and Eeyore.
But now it appears one of the bear-of-little-brain's mates was forgotten along the way and condemned to anonymity for nearly 90 years.
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Winnie-the-Pooh gets a new friend
A new character will enter the Hundred Acre Wood on the 90th anniversary of Winnie-the-Pooh.
Finally, this century-old wrong is about to be righted and the residents of the Hundred Acre Wood will be joined by a new companion: Penguin.
Winnie-the-Pooh's story expands next month with the release of official sequel, Winnie-the Pooh, The Best Bear in All the World, written by author and broadcaster Brian Sibley to coincide with the 90th anniversary of the publication of Winnie-the-Pooh.
The characters in the series were inspired by Milne's son Christopher Robin's stuffed toys, but for whatever reason, Christopher Robin's penguin was forgotten.
It wasn't until Sibley spotted a photo of Milne and his son playing with the penguin that he realised there had to be a new addition to the iconic story.
Penguin is the first new authorised character introduced to the Pooh franchise since Milne's death in 1956, with the Milne estate giving Sibley the green light.
"I remembered seeing a photograph of father and son playing on the nursery floor with Winnie-the-Pooh and a penguin," Sibley told the UK Telegraph.
"The thought of Pooh encountering a penguin seemed no more outlandish than his meeting a kangaroo and a tiger in a Sussex wood, so I started thinking about what might have happened if, on a rather snowy day, Penguin had found his way to Pooh Corner."
The penguin was reportedly bought for Christopher Robin by his mother, Daphne Milne, who also purchased the stuffed animals that inspired Tigger, Piglet, Eeyore, Kanga and Roo.
Pooh Properties trustee Rupert Hill told the Telegraph he thought Penguin was a perfect fit.
"We think that Brian's Penguin is a charming and natural addition to the existing characters in the stories.
"We hope that this new anthology, written and illustrated in the style of AA Milne's original books, will bring great joy to readers old and new."
Christopher Robin's original toys arel on display at the New York Public Library.
Winnie-the Pooh, The Best Bear in All the World will be available in Australia on October 1.