The King, the Prince and Princess of Wales, and other members of the royal family came together for a funeral service in London for the Duchess of Kent.
Mourners filled Westminster Cathedral for the requiem mass, a Catholic funeral, the first to be held for a member of the royal family in modern British history.
The disgraced Duke of York made a rare appearance with his ex-wife Sarah, Duchess of York.
Andrew’s public career was effectively ended by his friendship with the late American financier and convicted sex offender Jeffrey Epstein, as was that of Britain’s former ambassador to the US, Peter Mandelson.
The 89-year-old Duke of Kent, using a walking stick, led other mourners into the cathedral.
Pope Leo XIV paid tribute to the Duchess of Kent, praising her "legacy of Christian goodness" and her "dedication to official duties" in a message delivered during the funeral mass.
At the end of the funeral, Andrew tried to exchange words with William as they stood on the cathedral steps, but while the King replied to his brother when they briefly met, William stared straight ahead and only very faintly nodded his head in response.
William had a white handkerchief tucked into his top pocket, while Kate wore a black hat with a large bow at the back and netting detail at the front, and pearl earrings, with her hair down at the back.
The King arrived without the Queen, who pulled out of the event on Tuesday morning as she was suffering from acute sinusitis.
A Buckingham Palace spokesperson said: “With great regret, Her Majesty the Queen has withdrawn from attendance at this afternoon’s requiem mass for the Duchess of Kent as she is recovering from acute sinusitis.
“Her thoughts and prayers will be with the Duke of Kent and all the family.”
The announcement raises questions over the role Camilla will be able to take in US president Donald Trump’s high-stakes state visit, which begins in full at Windsor on Wednesday and is being hosted by the King.
The Palace said the Queen hoped she would have recovered sufficiently to be able to attend all royal elements of the trip as planned, with highlights including a lavish state banquet.
Moments before the requiem mass began, the duchess's immediate family arrived, led by her daughter Lady Helen Taylor, walking arm-in-arm along the nave with her father, the Duke of Kent.
Other mourners included the Princess Royal and Sir Tim Laurence, the Duchess of Edinburgh, and the close family of the Duke and Duchess of Kent.
Former Formula One world champion Sir Jackie Stewart and actors Rula Lenska and Dame Maureen Lipman were also among the mourners at the funeral, which was conducted by Cardinal Vincent Nichols, leader of the Roman Catholic Church in England and Wales.
Andrew and Sarah sat at the end of a row. Kate sat across the aisle, wearing a four-strand pearl-and-diamond choker necklace that belonged to the late Queen Elizabeth II.
Katharine, the wife of the late Queen’s cousin the Duke of Kent, died peacefully at home, surrounded by her family, on the evening of 4 September, aged 92.
A devout follower of the Roman Catholic faith, in 1994 the duchess became the first member of the royal family to convert to Catholicism for more than 300 years, and it was her wish to have her funeral at Westminster Cathedral.
The Pope said: "I was saddened to learn of the death of Her Royal Highness the Duchess of Kent, and I send heartfelt condolences, together with the assurance of my prayerful closeness, to Your Majesty, the members of the royal family, and especially to her husband, the Duke of Kent, and their children and grandchildren at this time of sorrow.
"Entrusting her noble soul to the mercy of our Heavenly Father, I readily associate myself with all those offering thanksgiving to Almighty God for the duchess's legacy of Christian goodness, seen in her many years of dedication to official duties, patronage of charities, and devoted care for vulnerable people in society.
Bishop James Curry, Auxiliary Bishop of Westminster, highlighted the duchess's varied public life, from training to work with the Samaritans to visiting Lourdes and co-founding the music charity for young people Future Talent.
The bishop said: "Mrs Kent loved teaching children, knowing that a classroom is full of learners. Too often young minds, and ours, are solely defined by hurts, wounds and disappointments.”
After the requiem mass the senior royals and the duchess's family stood on the cathedral steps to watch her coffin being placed into a hearse for its final journey to the Royal Burial Ground at Frogmore, Windsor.
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