The Prince of Wales joined mourners at the private funeral of Lady Gabriella Kingston’s husband Thomas Kingston.
About 140 friends and family, including Lady Gabriella’s parents Prince and Princess Michael of Kent, attended the service at the Royal Chapel in St James’s Palace in London on Tuesday.
Mr Kingston died aged 45 on 25 February at his parents’ home in the Cotswolds.
An inquest heard that he had died from a “traumatic head wound”. A gun was found near his body.
The King – Lady Gabriella’s second cousin – was not present at the funeral as he is not attending public events while he undergoes cancer treatment.
Queen Camilla also did not attend. She was hosting a Women of the World reception at Buckingham Palace.
Mr Kingston’s coffin was brought from the chapel of Kensington Palace, accompanied by close family for the hour-long service.
The funeral was followed by a reception in St James’s Palace and a private cremation.
In a statement issued by Buckingham Palace shortly after Mr Kingston’s death, Lady Gabriella described him as “an exceptional man who lit up the lives of all who knew him”.
King Charles and Queen Camilla sent their “most heartfelt thoughts and prayers” to his family.
Lady Gabriella, 42, married financier Mr Kingston at Windsor Castle in 2019, with Queen Elizabeth II and the late Duke of Edinburgh among the guests.
Lady Gabriella is not a working royal, but she is a part of the Royal Family.
Her father, Prince Michael, aged 81, is the late Queen Elizabeth II’s first cousin and a grandson of King George V.
An inquest into Mr Kingston’s death opened on 1 March at Gloucestershire Coroner’s Court.
His death was not being treated as suspicious, and no-one else was involved.
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