Photo:Chris Jackson - Pool/Getty Images

Catherine, Princess of Wales and Prince William, Prince of Wales depart the Order Of The Garter Service at Windsor Castle

Chris Jackson - Pool/Getty Images

Kate Middletonis all smiles asPrince Williamtakes part in one of the oldest royal traditions: the Order of the Garter service.

The Princess of Wales, 41, supported her husband on Monday as he made his debut as the Prince of Wales at the Order of the Garter ceremony and procession at Windsor Castle. Kate watched as Prince William,King Charles, Queen Camilla and other members of the royal family donned ornate blue robes and hats featuring an ostrich plume at the prestigious event dating back centuries.

HENRY NICHOLLS/POOL/AFP via Getty Images

Catherine, Princess of Wales (C-L) and Britain’s Sophie, Duchess of Edinburgh (C-R) look at Britain’s Prince William, Prince of Wales (2nd R) and Britain’s Prince Edward, Duke of Edinburgh (R) arriving at St George’s Chapel to attend the Most Noble Order of the Garter Ceremony

In addition to the ceremony having historic roots, it is also a milestone in Prince William and Princess Kate’s relationship. Kate made her debut at the event in 2008 as William’s girlfriend when he received his Order of the Garter knighthood. Wearing an elegant black and white outfit, Kate was spotted chatting withPrince Harryand Camilla.

Kate’s attendance was significant, showing that she was being welcomed into the royal family fold.

The now-Prince and Princess of Wales met as students at the University of St. Andrews in Scotland. Three years after Kate’s outing at the Order of the Garter service, the pair married at Westminster Abbey.

Prince Harry, Kate Middleton and Camilla in 2008.Anwar Hussein/Getty Images

Prince Harry (L), Camilla, Duchess of Cornwall and Catherine Middleton (C) attend the service for the Most Noble Order of the Garter at St George’s Chapel

Anwar Hussein/Getty Images

Over the past 15 years, Kate has attended the Order of the Garter ceremony with the royal family on many occasions.

Kate accessorized with theCollingwood pearl and diamond earringsthat previously belonged to her late mother-in-law, Princess Diana. The jewels were a key part of Diana’s jewelry box, and Princess Kate has worn them on numerous occasions — sometimes pairing them with a tiara for glamorous palace events.

Prince William.HENRY NICHOLLS/POOL/AFP via Getty Images

Prince William, Prince of Wales arrives at St George’s Chapel to attend the Most Noble Order of the Garter Ceremony

At several points, Kate and those participating in the procession held onto their hats due to wind gusts.

The event coincided with a special day for Prince Edward and Sophie: their 24th wedding anniversary!

Mark Cuthbert/UK Press via Getty Images

Catherine, Princess of Wales and Sophie, Duchess of Edinburgh during the Order Of The Garter Service at Windsor Castle

The Most Noble Order of the Garter is the oldest British order of chivalry and the world’s oldest national order of knighthood. Membership of the order is limited to the monarch, the Prince of Wales, royals from the U.K. and abroad and just 24 Companions, and appointments are at the monarch’s sole discretion to recognize public service or personal service to the sovereign.

Several members of the British royal family are members including Queen Camilla, Princess Anne, Prince Edward, the Duke of Kent, the Duke of Gloucester and Princess Alexandra. Royals from around the world — such as King Felipe of Spain, King Willem-Alexander of the Netherlands, Queen Margrethe of Denmark, King Carl Gustaf of Sweden and King Harald of Norway — also hold the position.

King Charles and Queen Camilla.Chris Jackson - Pool/Getty Images

King Charles III and Queen Camilla arrive at the Order Of The Garter Service at Windsor Castle

Prince William and other Companions wore the Order of the Garter robe, or mantle, last month at King Charles and Queen Camilla’s coronation. For the crowning ceremony, Kate wore themantle of the Royal Victorian Order.Queen Elizabethnamed her granddaughter-in-law aDame Grand Cross of the Royal Victorian Orderin April 2019, coinciding with Kate and William’s eighth wedding anniversary.

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Catherine, Princess of Wales waves as she arrives at St George’s Chapel to attend the Most Noble Order of the Garter Ceremony

source: people.com