Archie's Jeans and George's Shorts! How the Royal Style Rules Differ for Each Family

Samir Hussein/WireImage

Meghan Markle, Prince Harry and their children Archie and Lili showcased a California-casual look in their 2021 holiday card, but one piece of clothing will be of particular interest to royal watchers: Archie's jeans!

The 2-year-old is blazing a relatively new fashion trail for members of the royal family, who typically keep their young boys in shorts until they are 8 years old — just ask Prince George.

Prince William and Kate Middleton's older son, who just marked his 8th birthday in July, has only recently graduated to more grownup attire after appearing in shorts and knee socks for most of his life until this year.

The only notable exceptions to this rule — which can also be seen in the clothing worn by George's younger brother, 3-year-old Prince Louis — were when George went country-chic in blue trousers tucked into Hunter boots for the Cambridges' 2018 holiday card shot at their Norfolk-based Anmer Hall estate, and when the formality of Prince Harry and Meghan's May 2018 wedding called for a military-style ensemble similar to those worn by his uncle and father (with one sweet, personalized touch).

George's go-to signature look as a young boy is "definitely a look for the royals," Sophie Mirman, founder of royal favorite children's wear store Trotters, told PEOPLE this summer, "and there is this rather strange thing in English schools where children have to wear shorts, even in the winter, with their freezing cold knees — it's almost like an unwritten code."

Alexi Lubomirski

On the other hand, Archie — who relocated to the U.S. with his parents last year and welcomed his baby sister on June 4 — is subject to looser style guidelines since Harry and Meghan have stepped back as working members of the royal family.

As for Meghan, she and her sister-in-law Kate each quickly picked up royal dressing and etiquette before they married into the House of Windsor.

Stephen Pond/Getty Images Kate Middleton and Meghan Markle

For starters, nude tights — or pantyhose, which have long been a staple of Kate's wardrobe (Princess Diana was also a fan) — are an unofficial royal mandate.

Though Meghan stepped out in bare legs for her and Harry's engagement photo call in November 2017, she slipped into some sheers for her first public appearance as a newlywed three days after the couple's May 2018 wedding. (A few months later, the Duchess of Sussex diverged from the traditional royal manicure — also sheer and neutral — with black polish.)

Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more!

In the Sussexes' new holiday card, Meghan eschews the "Duchess Slant," and Harry goes barefoot — a royal holiday card first for the Duke of Sussex! Earlier this month, William also broke tradition in a pair of shorts in the Cambridge family's 2021 holiday card.

RELATED: Kate Middleton and Prince William's Christmas Card Easter Eggs Explained!

Max Mumby/Indigo/Getty; Alex Lentati/WPA/Getty; Mark Cuthbert/UK Press/Getty; REX/Shutterstock

As for the woman at the helm of the royal family, Queen Elizabeth, she has her own style code: cheery and bright!

The Queen's rainbow wardrobe is both chic and practical. Daughter-in-law Sophie, Countess of Wessex said in the 2016 documentary The Queen at 90: "She needs to stand out for people to be able to say 'I saw the Queen.' Don't forget that when she turns up somewhere, the crowds are two, three, four, 10, 15 deep, and someone wants to be able to say they saw a bit of the Queen's hat as she went past."