The Duke of Kent, the oldest working member of the royal family, was joined by his wife the Duchess of Kent as he was serenaded with Happy Birthday on the bagpipes on the day he turned 89.

Edward, the late Queen’s cousin, watched alongside Katharine, 91, who was pictured for the first time sitting in a wheelchair, with a blue shawl around her shoulders, outside the entrance of their Kensington Palace home, Wren House.

It was a rare appearance for the duchess, who did not attend the Platinum Jubilee celebrations, nor the late Queen’s funeral or the King’s coronation.

Katharine, who prefers to be known as Mrs Kent, dropped her HRH style and retreated from royal life to spend more than a decade teaching music in a state primary school in Hull.

Also there for the birthday celebrations was the duke and duchess’s son Lord Nicholas Windsor and the duke’s younger brother Prince Michael of Kent, 82.

The family watched as three pipers from Royal Scots Dragoon Guards (Carabiniers and Greys) performed tunes including Happy Birthday, Hills Of Biggar and Scotland The Brave in the open air on Wednesday.

The duke served as an officer in The Royal Scots Greys, which eventually became the Royal Scots Dragoon Guards, between 1955 and 1971 and was posted to Hong Kong, Cyprus and Northern Ireland. He is its deputy colonel-in-chief.

After the rendition, Edward, holding a walking stick, shook hands with and chatted to the pipers, who were dressed in their red tartan kilted uniforms, thanking them for their well wishes.

Dubbed “Steady Eddie”, the duke has become known for his dependability during his decades of royal service.

He performed a key supporting duty during Queen Elizabeth II’s Platinum Jubilee celebrations, just three months before her death.

The two appeared on the balcony together, standing side by side, as the duke took the salute of the passing soldiers after Trooping the Colour.

Birthday wishes were posted on the royal family’s official social media accounts, showing the duke, who has appeared frail in recent years, carrying out royal engagements despite being just one year from 90.

Last week, he joined the King at a reception to celebrate the Commonwealth diaspora ahead of Charles’s tour to Samoa, and attended a concert.

He also held a meeting in his role as the country’s top Freemason – the secret society’s Grand Master of the United Grand Lodge of England.

The duke is perhaps best known for being the former president of the All England Lawn Tennis and Croquet Club and presenting the Wimbledon trophies each summer, while the duchess is famed for consoling losing Wimbledon finalists, notably a tearful Jana Novotna in 1993.

Alongside the Princess of Wales, the duke is joint president of the Scout Association.