The royal children all wore this in their first birthday portrait

The Duchess of Cambridge is known for re-wearing a lot of her clothes, and she applies the same principle to her three children: Prince George, Princess Charlotte and Prince Louis.

In fact, she sometimes dresses them in her favourite children's clothes, regardless of their gender. For example, you might not have noticed, but in each of their first birthday portraits, the babies wore the exact same shoes.

Prince George

Prince George
(Image credit: PA)

In his shot, Prince George wore cute blue dungarees, paired with navy blue leather shoes. Then, Kate photographed Princess Charlotte for her milestone birthday, wearing a blue floral dress with a white cardigan, and those same shoes.

(Image credit: HRH Duchess of Cambridge)

Whilst you can't see the shoes in Prince Louis' birthday portrait, also taken by the Duchess this year, we can imagine he wore the same shoes as well.

It's very traditional for clothes to be passed down different children in the royal family, and in fact Prince George and Louis have both been snapped wearing ensembles that used to belong to Prince Harry and Prince William back in the 80s, which is very lovely indeed.

Not to mention sustainable.

Penny Goldstone

Penny Goldstone is the Digital Fashion Editor at Marie Claire, covering everything from catwalk trends to royal fashion and the latest high street and Instagram must-haves.

Penny grew up in France and studied languages and law at the Sorbonne Nouvelle University in Paris before moving to the UK for her MA in multimedia journalism at Bournemouth University. She moved to the UK permanently and has never looked back (though she does go back regularly to stock up on cheese and wine).

Although she's always loved fashion - she used to create scrapbooks of her favourite trends and looks, including Sienna Miller and Kate Moss' boho phase - her first job was at MoneySavingExpert.com, sourcing the best deals for everything from restaurants to designer sales.

However she quit after two years to follow her true passion, fashion journalism, and after many years of internships and freelance stints at magazines including Red, Cosmopolitan, Stylist and Good Housekeeping, landed her dream job as the Digital Fashion Editor at Marie Claire UK.

Her favourite part of the job is discovering new brands and meeting designers, and travelling the world to attend events and fashion shows. Seeing her first Chanel runway IRL at Paris Fashion Week was a true pinch-me moment.