The Spanish designers chosen by Princess Kate reveal all the details on the royal siblings adorable looks

By Monique Jessen
Updated October 05, 2016 06:19 PM
Credit: Annie Leibovitz

Posing for a picture with Gan-Gan has never looked so stylish!

Nestled proudly in Queen Elizabeth‘s lap, Princess Charlotte showed off a brand new toothy smile – and an adorable new outfit – when she posed alongside big brother Prince George for the famed photographer Annie Leibovitz in a new picture released on Thursday to celebrate the Queen’s 90th birthday.

And the almost 1-year-old could not have looked cuter! Wearing a dainty floral print dress with a frilled collar and matching bloomer-style knickers from Madrid-based brand m&h – it’s a very similar look to what the tiny tot has worn previously.

“We are very proud that Princess Charlotte is wearing m&h again!” Margarita Pato, founder and director of the Spanish high-street brand tells PEOPLE exclusively, revealing that the dress was from their Autumn/Winter 2015 collection and is no longer in stock. Retailing for $34, the material is described as a “patterned viyella.”

Want to keep up with the latest royals coverage? Click here to subscribe to the Royals Newsletter.

Worn under a $54 beige knitted cardigan from the online Spanish childrenswear boutique Pepa & Co., the company had no idea that Princess Kate was a customer. The microfiber cardigan, which features pearlized buttons, is currently on sale for just $27.

“We are delighted that Spanish brands have once again been selected again for Princess Charlotte and Prince George for the royal photo,” Pepa Gonzalez, founder of Pepa & Co. tells PEOPLE. “We believe that the Duchess of Cambridge is drawn to these elegant clothes – which are more formal yet nostalgic in appearance – because of their timeless appeal.”

Keeping cozy in her $16 Amaia tights, Charlotte also debuted her first pair of Early Days shoes – a brand that Kate also chose for George at a similar age.

The British heritage brand, which has been in business since 1952, is sold at one of Kate’s favorite children’s clothing stores in London – Trotters. The Emma Pre-Walkers in white worn by Charlotte retail for $40 and are made from “buttery soft Italian leather.”

The Leicester-based firm has barely been able to keep with demand since Prince George wore their Alex Pre-Walker shoes on tour with his parents in New Zealand in 2014.

“It’s been manic ever since Prince George first wore our shoes,” Paul Bolton, managing director of Early Days, tells PEOPLE, adding: “Things have really snowballed, but it’s a good problem to have!”

[BRIGHTCOVE “21001609” “” “peoplenow” “no” ]

The world’s most fashionable toddler, Prince George, stands next to his little sister in Kate’s favorite look for him – shorts teamed with a Fair Isle style jumper (over a Peter Pan collar white top) and, of course, his $10 signature Amaia knee-high socks in navy, which he has in several colors.

The knitwear is from Fina Ejerique, a Spanish brand that George wore previously in photos released by the palace during Christmas 2015. This time, Kate chose a navy style in a wool blend, which retails for $51 and is also from their Autumn/Winter 2015 collection.

“George looks so cute, he’s a beautiful boy,” Ana Perez, creative director of the brand, tells PEOPLE. “Our happiness is indescribable! To be chosen to be part of the historical portrait of HM Queen Elizabeth with her grandchildren and great-grandchildren is something we could not have imagined even in our dreams.”

Worn with his trusty Start-rite Jo shoes in navy, and his blonde locks combed over to the side just like Charlotte’s – the pair certainly have their royal poses practiced to perfection.

“I think they all look adorable and it looks very natural,” says Amaia Arrieta, who owns the eponymous boutique at which Kate shops, adding: “The Queen must be very proud to show off all her grandchildren.”

Reporting by NINA BIDDLE