Kate Middleton is keeping the memory of Princess Diana close to her heart during King Charles III’s Trooping the Colour. 

The Princess of Wales stunned in an elegant green coat dress with bejeweled embellishments.

While Kate made her first appearance at Trooping the Colour as the Princess of Wales, she came dressed to the occasion with her gold Cartier shamrock brooch and completed her look with diamond drop earrings that previously belonged to her late mother-in-law Princess Diana. 

TROOPING THE COLOUR KICKS OFF KING CHARLES’ OFFICIAL BIRTHDAY PARADE AS MONARCH

Kate Middleton Trooping the Colour

Catherine, Princess of Wales travels down The Mall in a horse drawn carriage during Trooping the Colour on June 17, 2023 in London, England. (Getty Images)

Princess Diana wore the diamond earrings during a royal event in 1995. She was photographed wearing a full-length sleeveless black evening dress while holding a bouquet of flowers.

Princess Diana

British royal Diana, Princess of Wales wearing a full-length sleeveless black evening dress, holds a bouquet of flowers at an event, circa 1995. (Getty Images)

During the Trooping of Colour, Princess Kate topped off her look with a matching green hat to go with her gorgeous ensemble. 

As the Princess of Wales honored Princess Diana, her remarkable green outfit choice and shamrock brooch was a nod to her new colonelcy of the Irish Guards.

Last December, King Charles appointed Princess Kate to colonel of the Irish Guards. The title previously belonged to Prince William.

KING CHARLES TO RESTORE TROOPING THE COLOUR ROYAL TRADITION FOR THE FIRST TIME IN OVER 30 YEARS

Queen Camille Kate Middleton

Prince George of Wales, Catherine, Princess of Wales and Queen Camilla ride in a horse drawn carriage during Trooping the Colour at Horse Guards Parade. (Getty Images)

At the momentous Trooping of Colour event, the Princess of Wales rode in the royal carriage with her and Prince Williams’ three children — Prince George, Prince Louis and Princess Charlotte — alongside Queen Camilla.

Princess Kate and Prince Williams 3 kids

Britain's Prince George of Wales (R), Britain's Prince Louis of Wales (C) and Britain's Princess Charlotte of Wales (L) arrive in a horse-drawn carriage on Horse Guards Parade for the King's Birthday Parade, 'Trooping the Colour.' (Getty Images)

Princess Kate was seen lovingly fixing Prince Louis’ tie in an adorable moment during the royal carriage ride. 

Princess Kate fixing Prince Louis

Princess Kate was seen lovingly fixing Prince Louis’ tie in an adorable moment during the royal carriage ride.  (Getty Images)

Trooping the Colour, a ceremony marking the official birthday of King Charles III, celebrated a very special tradition for the first time in more than 30 years. 

KING CHARLES III ANNOUNCES FIRST TROOPING THE COLOUR, REVEALS NEW TITLES FOR ROYAL FAMILY

King Charles saddled up Saturday to participate in the annual Trooping the Colour as sovereign on horseback. This was the first time a reigning monarch had ridden in the parade since his mother, Queen Elizabeth II, in 1986.

Queen Elizabeth II on horseback in 1986

14th June 1986:  Queen Elizabeth II performs a smart salute during the Trooping the Colour ceremony in London. (Getty Images)

Britain’s longest-reigning monarch, Queen Elizabeth II, passed away in September. She was 96.

For the historic celebration, King Charles' event boasted over 1,400 parading soldiers, 200 horses and 400 musicians for the royal tradition.

Trooping the Colour

Troops advance down the Mall during Trooping the Colour on June 17, 2023 in London, England. Trooping the Colour is a traditional parade held to mark the British Sovereign's official birthday. (Getty Images)

CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER

His Majesty took the Salute as Colonel in Chief of the seven regiments of the Household Division.

King Charles Trooping the Colour

His Majesty King Charles III took the Salute as Colonel in Chief of the seven regiments of the Household Division. (Getty Images)

Prince William, Prince Edward, Princess Anne and members of the British royal family traveled by horse-drawn carriage or on horseback following Charles’ entrance.

CLICK HERE TO GET THE FOX NEWS APP

Trooping the Colour

King Charles III, Queen Camilla and members of the royal family stand on the balcony of Buckingham Palace to watch a fly-past of aircraft by the Royal Air Force during Trooping the Colour. (Getty Images)

The king led the procession to Buckingham Palace and took another salute from the dais.

The Trooping of Colour concluded with the royal family gathering out on the palace balcony. The Royal Air Force soared to the skies and performed a colorful flypast in a sweeping finale. There was also a 41-gun salute fired from nearby Green Park.