The Queen and Prince Philip, Duke of Edinburgh, are celebrating their 73rd wedding anniversary today.

To mark the occasion Buckingham Palace has released a heart-warming image of the Royal couple looking at a homemade card made by their great-grandchildren Prince George, Princess Charlotte and Prince Louis.

The colourful homemade gift is emblazoned with the number 73 – that pops out from the front of the card.

In the touching image, the Queen and Duke are sat on a sofa in Windsor Castle’s Oak Room and appear to be reading the card’s message from George, a future king, and his siblings.

The picture, taken by Chris Jackson from Getty Images, also shows a small pile of anniversary cards and letters sent by well-wishers on a nearby table.

The monarch, 94, was a 21-year-old princess when she married the dashing Lieutenant Philip Mountbatten at Westminster Abbey on November 20, 1947.

British people were still experiencing heavy rationing and shortages when the couple were married.

The country had endured one of the worst winters in living memory a few months earlier.

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But the royal wedding gave the nation a brief chance to share in the happiness of a royal wedding day and to look forward to more prosperous times.

Their enduring relationship has lasted the longest of any British sovereign and Philip has been at the Queen’s side throughout the decades, supporting her as she devotes herself to her role as head of state.

The Queen and the duke, who has retired from public duties, are spending the lockdown in England isolating at Windsor Castle, and anniversary celebrations are expected to be low-key.

There is no traditional gift, jewel or colour associated with 73rd wedding anniversaries in the UK.

In the new photograph, the Queen is wearing a pale blue double wool crepe dress by Stewart Parvin and a chrysanthemum brooch made from sapphires and diamonds set in platinum, while Philip wears a blazer, shirt, tie and trousers.

The past year has been a tumultuous one for the nation, with people learning to live with coronavirus that has had a profound impact on all aspects of society.

Royal events moved online during the first national lockdown, with the Queen holding virtual engagements via video calls and meetings by phone.

The Queen and Prince Philip's long union is seen as a key source of stability within the monarchy.

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Together they have celebrated the silver, golden and diamond jubilees of the Queen’s reign, and faced ups and downs over the years including the breakdown of three of their four children’s marriages, and the backlash which followed the death of Diana, Princess of Wales.

On their golden wedding anniversary in 1997, the Queen paid a touching tribute to her husband, saying: “He has, quite simply, been my strength and stay all these years.”

Philip used the occasion to praise the Queen for her abundance of tolerance.

“I think the main lesson that we have learnt is that tolerance is the one essential ingredient of any happy marriage,” he said.