Prince Louis.Photo: Mark Kerrison/In Pictures via Getty

Prince Louis, 4, arrives with Catherine, Princess of Wales, to attend the Easter Sunday church service at St George’s Chapel in Windsor Castle on 9 April 2023 in Windsor, United Kingdom. Easter Sunday is the focal point of the Royal Family’s Easter celebrations and this will be the first without Queen Elizabeth II. (photo by Mark Kerrison/In Pictures via Getty Images)

Prince Louisis growing up, which means a change in his royal style.

The young prince, who will celebrate his 5th birthday on April 23, made hisEaster debutwith the royal family for their annual holiday church outing on Sunday. Prince Louis held hands with momKate Middletonas they trailed closely behind dadPrince William, brotherPrince George, 9, andPrincess Charlotte, 7, as they made their way to St. George’s Chapel in Windsor Castle for the service.

“It was wonderful to see the three royal children join their parents in the spring sunshine for the traditional Easter Sunday service,” Riley tells PEOPLE. “We were delighted to see thatPrincess Charlottewas wearing our navy mini floral frill dress; she looked so pretty and comfortable. A printed cotton dress with puffed sleeves and a Peter Pan collar is a perfect look for a girl of her age. The blue and ivory floral print on a navy background coordinated perfectly with the rest of her family. They all lookedso harmonious in blue.”

Yui Mok - WPA Pool/Getty

WINDSOR, ENGLAND - APRIL 09: Catherine, Princess of Wales and William, Prince of Wales are seen with Princess Charlotte and Prince Louis after attending the Easter Mattins Service at St George’s Chapel at Windsor Castle on April 9, 2023 in Windsor, England. (Photo by Yui Mok - WPA Pool/Getty Images)

WhilePrince Georgewore a suit and tie for the Easter outing, as hehas in recent years,Prince Louisstuck to the classic look for upper-class boys in Britain: shorts with knee socks. But for the first time, Louis wore a tie and blazer.

“Prince Georgeis older now and so wears long trousers,” explains Riley. “This was the first time we saw his little brother Louis wear a blazer and tie in public, and the fact that the Princess of Wales chose sky blue rather than navy made the outfit more fun and age-appropriate. He also matched perfectly with his mother and sister, something which he can still do as the youngest sibling.”

WINDSOR, UNITED KINGDOM - APRIL 09: (EMBARGOED FOR PUBLICATION IN UK NEWSPAPERS UNTIL 24 HOURS AFTER CREATE DATE AND TIME) Prince Louis of Wales and Catherine, Princess of Wales attend the traditional Easter Sunday Mattins Service at St George’s Chapel, Windsor Castle on April 9, 2023 in Windsor, England. (Photo by Max Mumby/Indigo/Getty Images)

BeforePrince Louis,Prince Georgewas known for hisshorts and knee socks combinations— even in the winter.

Thefirst time that Prince George wore long pants in publicwas in May 2018 at his unclePrince Harry’s wedding toMeghan Markle. As a page boy, George wore aminiature version of the Blues and Royals coatthatHarryand Prince William wore for the ceremony.

By the following year, Prince George veered more towards long pants, including for the traditionalChristmas day walk to churchin Sandringham in 2019 and aphotowithQueen Elizabeth, then-Prince Charlesand Prince William that was released a few weeks later.

Prince George, Prince Louis and Princess Charlotte.Karwai Tang/WireImage

LONDON, ENGLAND - JUNE 02: Prince George, Prince Louis and Princess Charlotte in the carriage procession at Trooping the Colour during Queen Elizabeth II Platinum Jubilee on June 02, 2022 in London, England. The Platinum Jubilee of Elizabeth II is being celebrated from June 2 to June 5, 2022, in the UK and Commonwealth to mark the 70th anniversary of the accession of Queen Elizabeth II on 6 February 1952. Trooping The Colour, also known as The Queen’s Birthday Parade, is a military ceremony performed by regiments of the British Army that has taken place since the mid-17th century. It marks the official birthday of the British Sovereign. This year, from June 2 to June 5, 2022, there is the added celebration of the Platinum Jubilee of Elizabeth II in the UK and Commonwealth to mark the 70th anniversary of her accession to the throne on 6 February 1952. (Photo by Karwai Tang/WireImage)

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AlthoughPrince Georgeis now a pro at sporting asuitat events (andtying his own tie, according to Princess Kate!), he returned to his signature style from his younger years with hisnew school uniformin photos released in September for the Wales kids' first day.

source: people.com