Duchess Kate brings her kids to enjoy new garden she designed for early childhood development

The royals visited the RHS Back to Nature Garden at the Chelsea Flower Show.

Kate, the Duchess of Cambridge, unveiled the "Back to Nature" garden she helped design at the RHS Chelsea Flower show this weekend.

The duchess' garden was created with a particular purpose -- to encourage children to play outside -- tying into the focus of her work on how important the early years of life are in childhood development and in setting the stage for a child's future.

"I believe that spending time outdoors when we are young can play a role in laying the foundations for children to become happy, healthy adults,” she said, speaking ahead of the garden unveiling.

The garden, designed by the duchess and award-winning landscape architects, is "a woodland setting for families and communities to come together and connect with nature," according to Kensington Palace. It includes a swing seat and a high platform tree house, inspired by a bird or animal nest and made from chestnut, with hazel, stag horn oak and larch nest cladding.

Kate, 37, has made early childhood development the focus of her work, advocating for the benefits of the outdoors on improving mental health, particularly for kids.

“Understanding that our brain develops to 90% of its adult size within these first five years helps crystallise how our experiences in these earliest years are so impactful, and influences who we become as individuals. What happens in our early years is vital to our being able to engage positively in school, and in work and society, and ultimately, to how we bring up our own children,” she said in a press release.

On Sunday, Kate, along with her husband Prince William, brought her own children around the garden and shared photos from the special family outing.

Prince George, Princess Charlotte and Prince Louis helped their mom, the duchess, gather moss, leaves and twigs to help decorate the garden, according to the palace. Hazel sticks collected by the family were also used to make the garden’s den.

A photo of Louis joyfully playing with a stick while running towards the camera stole the show.

In one sweet photo, George and Charlotte dangled their feet in the water of a stream below.

Kate posed for a photo on the swing seat in the garden. Charlotte and Louis -- with Prince William's help -- took a turn too!

Among the flowers spotted in the garden are forget-me-nots. The small blue flowers, which were a favorite of Princess Diana, her late mother-in-law, may be a tribute to Diana's influence and legacy.

Kate has said that providing children with the opportunity to spend time outdoors can play an important role in their overall well-being.

“I really feel that nature and being interactive outdoors has huge benefits on our physical and mental well-being, particularly for young children," the duchess said in an interview with the BCC for the garden's unveiling. "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.”