The book was written for primary-aged children and Professor Harper hoped William and Kate would save it for when Prince George was older.
He said children seemed to like reading about what their grandfathers and great-grandfathers did and the illustrations by Jenny Cooper really brought the story to life.
Professor Harper is launching his eighth children's book, Jim's Letters, next week. It tells the story of Gallipoli and he hoped the young Prince might be given that book when he next visits.
The book will be given to the royal couple by David and Andrew Blyth, the grandson and son of Lieutenant Colonel Curly Blyth who led the liberation of Le Quesnoy on November 4, 1918. David Blyth also plans to give them a copy of his television documentary Our Oldest Soldier, which is the story of his grandfather's role in the taking of Le Quesnoy and said he was honoured to get his 20 seconds with the Prince.
Cambridge has several links with the French town including a sister city agreement signed in 2000. Le Quesnoy celebrates Anzac Day on the Sunday closest to April 25 each year to recognise what New Zealand did for it during World War I, while Cambridge reciprocates by holding an Armistice event on the closest Sunday to November 11.
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