Prince William and Princess Diana can't contain their giggles in rare personal video

The late royal treated her sons to an outing in October 1993

A rare video of Diana, Princess of Wales shows the late royal unable to control her giggles with her sons, Prince William and Prince Harry, as they enjoyed an impromptu day trip back in 1993.

The sweet footage shows the trio climbing aboard a carriage and setting off on a horse and trap ride at a museum in Wales.

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Locals gathered around as William and Harry, then aged 11 and nine respectively, joined their mother for the half-term October outing.

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WATCH: Diana and William can't contain their giggles during half-term trip

Harry can be seen grinning at his older brother and mother before he takes his seat. William appears to be trying his best to stifle his laughter as a giggling Diana sits opposite her eldest son.

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The Princes were dressed smartly in suits for their visit to Wales, while Diana wore one of her signature skirt suits.

HELLO! reported at the time that the Princess broke with royal tradition by boarding a British Rail Inter-city train at Paddington to Cardiff with her young sons as a half-term treat, after spending time with their father, Prince Charles, in Scotland.

The royals pictured at Thorpe Park in August 1993

William and Harry were exceptionally close to their mother, who sadly died in a car accident in August 1997. The siblings keep the Princess' memory alive and often talk about 'Granny Diana' to their own children.

In ITV's documentary Diana, Our Mother, Harry gave an insight into his mother's cheeky side, saying: "She was one of the naughtiest parents. She would come and watch us play football and, you know, smuggle sweets into our socks.

"And I mean like literally walking back from a football match and having sort of five packets of Starburst. And just the whole shirt was just bulging with sweets and then sort of looking around, open the tuck box, throw it all in, lock it up."

"She was very informal and really enjoyed the laughter and the fun," William added.

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