But an unearthed photograph shows a lesser known Royal appearance - at Prince Harry's Wetherby School sports day in 1991. Harry, six at the time, competed in several events, including a sack race.

       Pictures show the young Prince jumping to the end of the track, just behind first place.

       Diana, a competitive soul, left her shoes as well as royal tradition by the start line to go for gold in the Mother's Race.

       For many, participating in their children's school's sports day is a given - but to see a Royal participate is quite the shock.

       “I don’t go by a rule book, because I lead from the heart, not the head,” Princess Diana said in an interview in 1995.

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       The Princess of Wales was pictured racing in a long skirt besides the other mothers.

       Reportedly, she placed second in the race.

       This was not the first time trailblazing Diana participated in sports day activities with her sons.

       The late princess took part in the Mother's Races from 1987, where she reportedly crossed the finish line first.

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       In 1990, she came third.

       The Princess was annually seen sprinting barefoot in fabulous skirts while laughing with other mothers after.

       She was also pictured with young Harry after the activities in an adorable snap.

       William and Harry attended the school in London before joining Ludgrove School - and later Eton College.