He's walking! Prince Louis races around mom Kate Middleton's designer garden with George and Charlotte

He's barely just celebrated his first birthday on April 23, and now Prince Louis is walking! The royal toddler - who turned one on April 23 - showed off his new skill during a fun day out with his siblings Prince George and Princess Charlotte and mom and dad Kate Middleton and Prince William. The family dropped by the Chelsea Flower Show - the world's largest garden and flower exhibition - to visit a garden that was specially designed by the Duchess herself, with children in mind.

Kensington Palace released a series of pictures of the royals by Matt Porteous during their trip to Kate's Back to Nature garden - which she worked on with the help of award-winning landscape architects Andrée Davies and Adam White. And it's clear to see the mini VIP visitors were more than impressed with the results of their mom's hard work.

This is the first time we've seen Prince Louis walking - and he sure does look confident! The toddler zooms off on his own brandishing a twig under the watchful eye of his papa William while his older siblings go barefoot to climb up the waterfall behind him.

A royal source told HOLA!'s sister publication HELLO! "The Duchess wanted to show her children what she has helped to create. She’s spent a lot of time on this and they have noticed. Naturally she wanted them to try out the garden and its features."

Charlotte and her five-year-old brother George take a moment to dip their toes into the stream while dad shows Louis the fire pit between two dens built from Hazel branches the family collected themselves.

At the heart of the garden is a nine-tonne treehouse built on a huge chestnut trunk and clad in Staghorn Oak, Larch and Hazel branches. A ladder gives access to a viewing platform over the rest of the garden.

In a statement, Kensington Palace said: "Her Royal Highness is a strong advocate for the proven benefits the outdoors has on physical and mental health, and the positive impact that nature and the environment can have on childhood development in particular."

One of the garden's talking points is a fun swing made of rope, which Kate couldn't resist trying out. Her children also followed suit. "Over the past months, Prince George, Princess Charlotte and Prince Louis have helped the Duchess gather moss, leaves and twigs to help decorate the RHS Back to Nature Garden. Hazel sticks collected by the family were also used to make the garden’s den," read the official statement about the project.

With her hair up in braids and muddy feet, Princess Charlotte enjoys the garden's rope swing. Hours before her Charlotte and the other children visited, Kate joined the gardeners to help with the finishing touches to the woodland setting, which was created for families and communities to come together and connect with nature.

While the older children were able to explore and climb by themselves, their little brother needed a little extra help with some parts of the garden, which included edible plants such as wild strawberries, rhubarb, carrots and beetroot, while the trees included pear and cherry trees.

In an interview with celebrity gardener Monty Don for the BBC, Kate said: "I really feel that nature and being interactive outdoors has huge benefits on our physical and mental wellbeing, particularly for young children. I really hope that this woodland that we have created really inspires families, kids and communities to get outside, enjoy nature and the outdoors, and spend quality time together."