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.
The sweet footage shows the trio climbing aboard a carriage and setting off on a horse and trap ride at a museum in Wales in October 1993.
Locals gathered around as William and Harry, then aged 11 and nine respectively, joined their mother for the outing.
READ: 7 times Princess Diana took William and Harry to work with her
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.
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.
MORE: Princess Diana's wedding dress mishap that went unnoticed
MORE: Watch Princess Diana's reaction as Zara Phillips gives Prince William a kiss on the balcony - video
Diana with William and Harry at Thorpe Park in August 1993
The royal brothers are set to mark what would have been their mother's 60th birthday on 1 July with the unveiling of a statue of the late Princess at Kensington Palace.
It will be the first time Prince William and Prince Harry have reunited since the Duke of Edinburgh's funeral at St George's Chapel in Windsor in April. The Cambridges were seen walking alongside Harry after the moving service.
The Duke and Duchess of Sussex moved to the US last year after stepping back from royal duties and welcomed their second child, Lilibet Diana Mountbatten-Windsor, on 4 June.
Kensington Palace has previously said: "The Princes hope that the statue will help all those who visit Kensington Palace to reflect on their mother's life and her legacy."
Make sure you never miss a ROYAL story! Sign up to our newsletter to get all of our celebrity, royal and lifestyle news delivered directly to your inbox.