The Prince of Wales has joined mourners at the private funeral of Lady Gabriella Kingston’s husband Thomas Kingston.

About 140 close friends and family of the financier, whose sudden death left the royal family in shock, gathered at the Chapel Royal in St James’s Palace in London on Tuesday.

Lady Gabriella was joined by her parents Prince and Princess Michael of Kent and Mr Kingston’s family.

Heir to the throne William, the Duke of Kent and Princess Alexandra were among the members of the royal family who attended.

The King – Lady Gabriella’s second cousin – and the Queen were not present.

Charles is not attending public-facing events while he undergoes treatment for cancer, and the Queen was hosting a WOW (Women of the World) reception at Buckingham Palace.

Mr Kingston, 45, died on February 25 at his parents’ home in the Cotswolds from a “catastrophic head injury” and a gun was found near his body in an outbuilding, the opening of his inquest heard.

Mr Kingston’s coffin was brought from the chapel of Kensington Palace, accompanied by close family for the hour-long service which began at 11.30am.

The service was led by the Sub-Dean of the Chapels Royal, the Rev Canon Paul Wright, with a sermon by the former Bishop of London, the Rt Rev Richard Chartres.

The funeral was followed by a reception in St James’s Palace and a private cremation, but no details have been shared of Mr Kingston’s final resting place.

A larger scale memorial service is expected to be held in honour of Mr Kingston in due course.

Lady Gabriella, known as Ella, married Mr Kingston at St George’s Chapel, Windsor Castle, in 2019 with Queen Elizabeth II and her husband, Prince Philip, the late Duke of Edinburgh, among the guests.

She paid tribute to her husband in a joint statement with his family following his death, describing him as “an exceptional man who lit up the lives of all who knew him”.

Mr Kingston was a director of Devonport Capital, which specialises in providing finance for companies in “frontier economies”.

The Bristol University graduate had also worked in Baghdad, Iraq, working to procure the release of hostages after joining the Diplomatic Missions Unit of the Foreign Office.

Mr Kingston is survived by his father, former barrister Martin Kingston; his mother, Jill Kingston; and his sisters, Joanna Connolly and Emma Murray.

Although Lady Gabriella is not a working member of the royal family, she and Mr Kingston’s family are being supported by the royal household.

William is Lady Gabriella’s second cousin once removed – and they were both godchildren of the late King Constantine of Greece.