Queen Camilla wipes away a tear after her horse Desert Hero wins the King George V Stakes in 2023 - Max Mumby

The Queen “burst into tears” and the King “welled up” after a horse bred by Elizabeth II won at Royal Ascot the year after her death, according to John Warren, the late Queen’s long-serving bloodstock and racing adviser.

The 2023 win for Desert Hero, which was formerly owned by the late Queen, was “quite remarkable” in King Charles’s first Royal Ascot as sovereign, Mr Warren added.

“The King welled up, tears in his eyes, and the Queen burst into tears,” said Mr Warren, in a documentary about the 200th anniversary of the Royal Procession at Ascot.

He described the late Queen as “unbelievably knowledgeable” about the sport, saying she was an expert horse breeder who read the Racing Post cover to cover.

In 2013, the late Queen’s filly Estimate won the Gold Cup, making her the first reigning monarch to win as an owner.

King Charles and Queen Camilla inherited Desert Hero after Elizabeth II died in 2022 - Justin Tallis/AFP

Mr Warren said she was thrilled at the time, adding: “When she passed the post, it brought the house down… The Queen was really, really excited. It was a day to remember.”

Since the death of Elizabeth II, the King and Queen Camilla have carried on the royal support for horse racing.

William Haggas, a trainer, said about Desert Hero’s win: “To do it at Royal Ascot with a homebred of the late Queen’s – it doesn’t get better than that.”

They have four runners: Reaching High, the favourite for the Ascot Stakes on Tuesday; Rainbows Edge, which will run on Wednesday in either the Duke of Cambridge Stakes or Kensington Palace Stakes; Treasure, which is likely to run in the Kensington Palace Stakes on Wednesday; and The King’s Falcon, in the Golden Gates Handicap on Saturday.

The Duke and Duchess of Edinburgh are also stalwarts of the event, along with the Princess Royal and Zara and Mike Tindall.

Desert Hero, ridden by Tom Marquand, won on Day 3 of the Royal Ascot 2023 - David Davies/PA

This year marks the 200th anniversary of the Royal Procession, in which the King and his guests will travel by carriage along part of the course in front of the crowds.

The tradition began in the reign of George IV when, in May 1825, the King, accompanied by the Duke of Wellington, led four other coaches with members of the Royal party from Windsor Castle to Ascot.

To mark the anniversary, this year’s visitors to the Queen Anne Enclosure will be able to view one of the landaus from the Royal Procession on the ground floor of the Grandstand.

The documentary, which was broadcast on ITV1 on Sunday afternoon, is available to watch on YouTube.

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