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A PICNIC IN THE PARK
At just 10 months old, William had the full attention of his adoring mother (here, on a trip to New Zealand in 1983). Of learning that her firstborn was to be a boy, Diana told the BBC in a 1995 interview that it was an "enormous relief."
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HEIR AND HEIR ALIKE
Diana helped her matching towheaded sons William, 4, and Harry, nearly 2, navigate a safe landing at the Aberdeen Airport, where the family headed for a summer vacation in 1986. "It would have been a little tricky if it had been two girls," Diana told the BBC. "William's future being as it is, and Harry like a form of a back-up in that aspect."
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BIRTHDAY HIGH JINKS
At the annual Trooping the Colour ceremony in 1988, which marks Queen Elizabeth's official birthday (June 11), William, 5, smiled at the crowd while 3-year-old Harry stuck out his tongue – to mom Diana's chagrin – at the fans surrounding Buckingham Palace.
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HARRY'S FIRST DAY
Joining big brother Wills, 7, an excited Harry, almost 5, was dropped off on his first day at pre-prep school Wetherby by Diana on Sept. 11, 1989. In a classic Diana move, she broke with the traditional, royal approach to child-rearing – dispensing with governesses and arranging her official schedule around that of her boys.
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LIFE'S A BEACH
It was a sandy pile-up for Diana as she got in on the fun with Wills, 7, and Harry, 5, and her nephews during a 1990 New Year's getaway with her mother, Frances Shand-Kydd, on Necker Island, Sir Richard Branson's private hideaway in the British Virgin Islands.
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During the Waleses' trip to Canada in October 1991, Diana made time between touring an AIDS hospice and a women's shelter to join William, 9, and Harry, 7, on a visit to Niagara Falls, where the trio donned rain slickers for a wet and wild voyage on the Maid of the Mist.
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A REGAL CARRIAGE
With nanny Olga Powell and mom Diana, the young princes enjoyed an open-sleigh ride in Lech, Austria, on March 30, 1993.
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LET IT SNOW
In March of the following year, during their pre-Easter break, William, 11, and Harry, 9, returned to the slopes in Lech, Austria, with Mom for a week-long ski trip that had become an annual family tradition.
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Always making sure her boys balanced their royal duties with play, Diana had pre-teens Harry and William bracing themselves for a thrilling – and wet! – day at Britain's most popular amusement park, Thorpe Park, in 1993.
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A MOTHER'S PRIDE
With Harry, 10, looking on, Diana gave William, 13, pointers as he signed the traditional entrance book at Eton College on his first day, Sept. 6, 1995. The school was another break with royal tradition: The young prince enrolled at the venerable institution instead of the private boarding school Gordonstoun, an alma mater of his father Prince Charles and grandfather Prince Philip.
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A SUMMER TO REMEMBER
A year after her divorce (and a month-and-a-half before her sudden death), a carefree Diana spent a few idyllic days in July 1997 vacationing with Harry, 12, and William, 15 (not pictured), in Saint-Tropez – at the invitation of her new love interest Dodi Fayed's father.