When it comes to being the royal family’s leading fashion icon, 6-year-old Prince George is arguably second only to his mother, Kate Middleton. His posh combinations of shorts and knee socks always make a splash on social media and complement his cherub-cheeked grin in a way that long pants and short socks never could.

As it turns out, Prince George’s go-to ensemble is more about tradition than sartorial innovation: Historically, dressing your young sons in shorts helped indicate you were a high-class family in England.

“Trousers are for older boys and men, whereas shorts on young boys is one of those silent class markers that we have in England,” etiquette expert William Hanson told Harper’s Bazaar. “Although times are (slowly) changing, a pair of trousers on a young boy is considered quite middle class—quite suburban. And no self-respecting aristo or royal would want to be considered suburban. Even the Duchess of Cambridge.”

These days, it’s more about maintaining tradition than highlighting class division, and the Duke and Duchess of Cambridge are known for dressing their kids in affordable clothing. Today.com reports that a certain pair of red corduroy shorts that Prince George wore in 2016, for example, was the equivalent of only about $20.

The practice likely arose from “breeching,” a custom that began in the 16th century where boys wore gowns for a few years before switching to shorts (also known as breeches) and then pants when they were around 8 years old. So we’ll see George looking dapper in full-length trousers soon enough—he’ll turn 8 in July 2021, and he’s even worn pants in public a few times already, most notably to the royal wedding of Prince Harry and Meghan Markle.

It’s far from the only fashion rule that the royal family follows—find out about 15 other ones here.

[h/t Harper’s Bazaar]