A picture of Thomas Kingston and his wife Lady Gabriella Windsor, taken weeks before his death, is believed to be one of the last of the couple together.
The sudden death of Mr Kingston was announced by Buckingham Palace on Tuesday. He was 45 years old.
Two weeks ago, Mr Kingston and Lady Gabriella were pictured attending a celebration of Shakespeare at the Grosvenor House Park Lane Hotel in London.
Read more: Who was Thomas Kingston?
The couple were pictured numerous times inside the event on Valentine’s Day, with Lady Gabriella smiling next to her husband as the pair wore similar royal blue clothing.
Mr Kingston married Lady Gabriella – the daughter of the Prince and Princess Michael of Kent – in 2019 at St George’s Chapel in Windsor Castle, with Queen Elizabeth II and the Duke of Edinburgh among the guests.
The death of the financier, who was known as Tom, was described as a “great shock to the whole family”.
Paying tribute, Lady Gabriella said he was an “exceptional man who lit up the lives of all who knew him”.
The King and Queen also sent their “most heartfelt thoughts and prayers” to Lady Gabriella, who is known as Ella, and Mr Kingston’s parents and siblings.
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Lady Gabriella is the King’s second cousin. They are both great-grandchildren of King George V.
After graduating from the University of Bristol, Mr Kingston worked as a director of Devonport Capital, which specialises in providing finance for companies in “frontier economies”.
He was also a close friend of Pippa Matthews – the Princess of Wales‘s sister – and the pair were said to have dated in 2011.
After dating Lady Gabriella for several years. he proposed on the Channel island of Sark in August 2018.
Gloucestershire Constabulary said in a statement that his death is “not being treated as suspicious” and a file is being prepared for the coroner.