While the Princess carried out countless royal duties, she made sure she was there to do the school run and even took William and Harry along to some of her public engagements.
HELLO! takes a look at some of the sweetest photos of Diana taking her sons to work with her.
Diana was said to have broken royal protocol when she took a nine-month-old William on her and Prince Charles' tour of Australia in 1983. While the tot was largely kept out of the spotlight on the overseas visit, the family did organise a couple of official photo calls, where William was spotted walking for the first time in public.
WATCH: Princess Diana's sweetest moments with her boys William and Harry
Harry arrived in September 1984 and once again, doting mum Diana took her sons along on the royal yacht Britannia during an official visit to Venice in Italy with Charles in 1985.
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Diana treated William and Harry to an evening out when they attended the premiere of Hook in April 1992, to aid her patronage Great Ormond Street Children's Hospital. The young princes looked in awe as they walked the red carpet and got to meet the film's cast, including Robin Williams, who played Peter Pan, and Dustin Hoffman as Captain Hook.
The Princess proudly looked over at her young sons during the VJ Day 50th anniversary celebrations in August 1995. William and Harry were also regulars at big royal events, such as Trooping the Colour, from an early age.
Diana looked overjoyed to be reunited with her sons as they joined their parents on an official visit to Canada in 1991. The Princess, who looked stunning in an iconic Moschino suit, threw her arms around William and Harry for a hug as they boarded the royal yacht Britannia.
During the same royal tour, William and Harry joined their mother for a fun-filled ride on the vessel Maid of The Mist at Niagara Falls.
William and Harry accompanied Diana to a concert at the Royal Albert Hall in London in 1991 to raise funds for the Royal Marsden Hospital, of which she was patron at the time. The Princes have continued their mother's legacy within their own charity work and William became president of The Royal Marsden in 2007.
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