Buckingham Palace told CNN that the Queen had traveled to Sandringham, her home in Norfolk, eastern England, for a private holiday.
A photo released to mark the occasion shows the king standing between two shedding ponies named Bybeck Nightingale and Bybeck Katie. The photo was taken in Windsor Castle Square in March, according to the royal family’s Twitter account.
William and Catherine, the Duke and Duchess of Cambridge, sent a message to the Queen on social media on her birthday.
“I wish Her Majesty the Queen a very happy 96th birthday today!” Tweet reads. “He is an inspiration to so many in the UK, the Commonwealth and the world, and it is especially special that we are celebrating this platinum anniversary.”
Charles, Prince of Wales, and Camilla, Duchess of Cornwall, also sent a birthday message to the Queen.
“We wish Her Majesty the Queen a special 96th birthday as we celebrate her platinum birthday,” the couple wrote on Twitter.
To celebrate the unprecedented anniversary, a number of events will be held in the UK throughout the year – culminating in the four-day National Bank Weekend from Thursday 2 June to Sunday 5 June, known as the weekend.
Toy maker Mattel also announced a Barbie doll that looks like a queen to celebrate the anniversary.
Queen Elizabeth II Barbie wears an ivory dress, blue ribbon, and tiara. It will be on sale from Thursday.
The Queen recently revealed that she has become “very tired and exhausted” after the latest Covid-19 attack. The Saudi monarch tested positive for the virus in February.
But her grandson Harry, Duke of Sussex, said the Queen “was in good shape” when he saw her in mid-April.
“It was great to see her,” he said in an interview with NBC’s “Today” program broadcast Wednesday.
Before his grandmother turned 96, Harry said, “After a certain age, birthdays get boring.”
Speaking about his relationship with the Queen, Harry described it as “very private”, adding: “We talk about things you can’t talk about with anyone else.”
CNN’s Max Foster contributed to this report.
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