Prince William and Cousin Peter Phillips Relationship Through the Years
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Prince William and his eldest cousin, Peter Phillips, grew up together.

“We had great fun growing up on our holidays, going to stay with [Queen Elizabeth II] at Sandringham, Balmoral and Windsor and we were incredibly lucky to be able to share a lot of our childhood time with her,” Peter said during a 2016 appearance on Good Morning Britain. “We had a lot of fun and there was a lot of space for kids to run around in and it wasn’t just us, it was the Waleses [William and Harry], Freddie and Ella Windsor and the Gloucesters.”

Peter added, “So there was quite a gang of us growing up in that age and it was a lot of fun. We caused quite a bit of mayhem and chaos but, fortunately, I don’t think we broke too much.”

William and Peter are the two eldest grandsons of the late Queen Elizabeth and Prince Philip. Peter, the son of Princess Anne and ex-husband Captain Mark Phillips, was born in November 1977. Five years later, William was born to King Charles III and late ex-wife Princess Diana. (Peter’s sister, Zara Tindall, arrived one year before William.)

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Many of Queen Elizabeth II and Prince Philip’s grandchildren grew up together. The late regent’s only daughter, Princess Anne, was the first royal to expand her brood. The Princess Royal and then-husband Captain Mark Phillips welcomed son Peter Phillips in November 1977 and daughter Zara Tindall in May 1981. Less than one year after Zara’s […]

As William and Peter grew up, they remained close. They even walked side-by-side, alongside the Prince of Wales’ brother, Prince Harry, in the respective funeral processions for Elizabeth and Philip.

Keep scrolling to revisit William and Peter’s relationship through the years:

June 1982

William was the late queen’s third grandchild behind Peter and Zara. The trio had frequently spotted together at royal occasions since then, including annual Trooping the Colour festivities, Christmas morning walks at Sandringham Estate and during family trips.

Prince William and Cousin Peter Phillips Relationship Through the Years
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July 1986

Peter and William were both pageboys at the wedding of their uncle Prince Andrew and his now-ex Sarah Ferguson.

April 2005

Despite once not approving of Charles’ relationship with Queen Camilla, William and his brother went to their wedding at Windsor Guildhall. The siblings were seen arriving alongside Peter and Zara.

In the years that followed, William and Peter continued to step out at joint official appearances.

April 2021

Philip died in April at the age of 99. Instead of having a grand state funeral like most predeceased monarchs and their consorts, Philip opted for an intimate service at St George’s Chapel at Windsor Castle. His four children, Charles, Anne, Andrew and Prince Edward, marched behind his casket into the chapel. They were joined by William, Peter and Harry, with Peter standing in between his cousins.

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September 2022

Elizabeth died one year later at the age of 96. Before her state funeral at Westminster Abbey, all of her grandchildren — William, Harry, Peter, Zara, Princess Beatrice, Princess Eugenie, Lady Louise Windsor and James, Earl of Wessex — held a solemn vigil around her coffin as it laid in state at Westminster Hall.

Her Majesty’s casket was transported to Westminster Abbey on September 19 before a memorial service. Peter, flanked by William and Harry, joined the procession on foot.

Prince William and Cousin Peter Phillips Relationship Through the Years
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March 2024

Peter gushed about William’s marriage to Princess Kate Middleton following her cancer diagnosis.

“Her and William make a fantastic team together,” he told Sky News Australia. “Their kids are great, and they have the balance of public life and trying to be parents to three young children, which is always difficult.”

Peter added, “I think, as history has taught us, and anyone knows, you actually want to be there for your children when they’re of a certain age. You want to be able to go drop them off at school and pick them up from school and go and watch matches and be a part of their school lives. And I think that balance of doing the family life and also the public life, I think they’ve pretty much got that, bang on.”

William and Kate share sons Prince George and Prince Louis and daughter Princess Charlotte. Peter, for his part, coparents daughters Savannah and Isla with ex-wife Autumn Kelly.

Prince William and Cousin Peter Phillips Relationship Through the Years
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April 2024

Weeks later, royal sources told The Telegraph that Peter is more like a brother to William than simply a cousin. One insider is quoted as saying, “He’s always been that sort of slightly older brother to William, ever more so since Harry moved to America.”

Harry relocated across the pond with wife Meghan Markle in 2020 after stepping down from their positions as senior working royals. The step-down came amidst a feud with William, and Harry had claimed his older brother planted unkind stories about Meghan in the press. William, for his part, never addressed the claims.