Sylvia Galpin, of Knowle Hill, near Reading, Berkshire, and her twin brother, Gervase Craven, a college lecturer, had posed for the poster used in the London Underground, according to Mrs Galpin's daughter Fenella, who visited the firm's factory in Norwich to break the news.
It was the twins' uncle, William Grimmond, who did the artwork for the Underground poster, displayed for 20 years from 1947. Mrs Galpin confirmed that he used to sketch her plaits in his studio. And later, when he took the twins for a ride on the Underground, he had pointed to the poster and told them: 'There, that's it.'
But when Ken Holmes, a retired industrial reporter and now a consultant to Start-rite's public relations company, was given the job of writing a book to commemorate the company's bicentenary this year, he found that the origin of the famous image was not clear. Rudyard Kipling could have had a hand in it. So could a woman artist who died aged 102 in 1980. And then there was the Frinton connection . . .
A ripple in the backwaters of history? Not at all. A good product implies a good provenance. Which is why many firms have begun to look to their 'roots'. Start- rite is justifiably proud of its record. It was the first company to make sized shoes in 1792. Its pioneering multi-width children's shoes appeared in 1923. During the war, when other shoe firms were aiming for mere survival, it invested heavily in research into the growth patterns of children's feet. The medical profession was delighted and the royal family is still a customer.
No matter that, as winkle-pickers and trainers made their appearance in the Sixties and Seventies, some kids had to be dragged kicking and screaming to the Start-rite shop; the shoes were the first to spare children's feet from the danger of being deformed by ill-fitting footwear. But the mystery of the twins' identity has yet to be unravelled.
James Hanly, chairman of the company for 45 years until 1970, knew a wealth of anecdote about Start-rite. He could probably have told a tale or two about the original twins, but he carried most of his memories to the grave.
The new breed of managers who succeeded him in the Seventies, including the current chairman, his nephew David White, appear to have gathered a completely different collection of company stories.
Mr White's theory was that the image had been conceived by the company's advertising agent as he drove back to London from Norwich through a forest in 1947. The trees had reminded him of a drawing by Rudyard Kipling illustrating one of his Just So Stories - The Cat Who Walked On His Own. But then Mr White was sent a pastiche of the Start-rite twins illustration which had appeared in an RAF magazine, Tee Emm, one of a series of humorous adaptations of well-known advertisements of the day. The trouble was that it had appeared during the war - years before the adman's vision on the road to London.
A further complication arose a couple of years ago, when Bill Wilkinson, a travelling salesman, told Mr White that his father, Joe, had painted the original poster in 1938. At the time, Joe had been production manager at Stanley Studios, Sheffield, a lively advertising agency.
Joe's widow, Louise Wilkinson, who lives in Frinton, told me - just as she told Mr Holmes when he was trying to unscramble the story - that she remembered the original artwork. Her husband, a watercolour artist, had not been good at drawing hands or faces, hence the back view. She had pulled his leg about it.
Stanley Studios? Bombed in 1940, said Mrs Wilkinson. She remembered it clearly. And the London Press Exchange advertising agency, which employed Sylvia and Gervase's uncle, William Grimmond? Also flattened in the Blitz. After that, Mr Grimmond worked at his own studio at Rowledge, Surrey, where the twins visited him. But no original artwork for the poster survives.
When Ken Holmes began poring over the bundles of documents in the company safe he found a lead to another suspect. This was a letter written in 1978 by Start-rite's old boss, James Hanly, congratulating an artist named Susan Pearce on her 100th birthday. In it, Mr Hanly recalls that the Start- rite twins poster was his idea 'many years ago'; and he congratulated Mrs Pearce on her 'very fine work of art'.
The firm's own advertising department could not elaborate. Its records were lost in a flood in 1987. But one undated illustration on the back cover of a pamphlet survives - showing an altogether different pair of twins. They are clad in summer rather than winter clothes. The boy is carrying a fishing rod and tiddler jar. The girl has plaits, and slung over her shoulder is a lunch box - or is it a gas-mask case?
The slogan is not the familiar 'Children's shoes have far to go', which appeared on the posters until they were retired in 1970, but the words 'Well begun is half done]'
So who did draw the original? Mrs Wilkinson says her husband Joe would never have used the type of lettering which appears on it. And the foliage and purplish colouring do resemble that of a surviving watercolour by William Grimmond showing the road between Rowledge and Frencham.
The players in this historical mystery take it lightly - even Sylvia Galpin and Gervase Craven, who thought they were Start-rite's originals until Mr Holmes put some tactful words in their ears. Neither has ever been a combative claimant.
Mrs Galpin says: 'I don't think we were the originals. It was just that over the years there were different versions of the poster and our uncle worked on the Underground one.'
But she is convinced she once saw a twins poster with her Uncle William's signature on one of the trees. None of the public and private archives I consulted could come up with a copy.
I also consulted a professional company historian, Dr Andrew Duncan, who suggested, besides the sources researched by Mr Holmes, that I consult the poster's printer (if known), put appeals in trade journals and the reference book Picture Sources UK (edited by Rosemary Eakins, last published in 1985 by Macdonald at pounds 45 and now out of print) which lists picture agencies, libraries, archives, collections, galleries, museums and universities.
'Of course,' Dr Duncan said, 'if all that was required was a copy of the picture, then I would go to a colour magazine of the day.'
If any collectors think they can throw light on this mystery, I would be glad to hear from them.
Meanwhile, twins who were dressed as the Start-rite twins in fancy-dress contests still half-believe they were the originals. Some Start-rite employees, Mr Holmes said, have always been convinced they were the models. The saga indicates that company directors should avoid bombing and flood, think twice before having company records chucked into the skip, and should remember that even the most august boardroom can breed modern myths.
If, in some attic, archive or magazine, a Start-rite twins poster should appear with a tree signed by William Grimmond, it would make one particular pair of Start- rite twins very happy.
Two Centuries of Shoemaking: Start-rite 1792-92 by Ken Holmes ( pounds 14.95 post free from Start-rite Shoes, Crome Road, Norwich NR3 4RD).
Dr Andrew Duncan, 19 Rainham Road, London NW10 5DL