Princes George and Louis, and Princess Charlotte appear in new video for a cause

Prince George, Princess Charlotte, and Prince Louis are supporting their mother, the Duchess of Cambridge, as she encourages young children to "Find Your Brave."

The three royal children have featured in a video made in support of Children's Mental Health Week, which runs from February 3 to 9. The short clip was posted in a story on Kensington Palace's Instagram account.

The video shows Kate Middleton carrying out her royal duties with children, including when she made dens with Scouts at Gilwell Park in Essex last March and when she along with husband Prince William tried kayaking during a trip to Northern Ireland last February, reports Hello!

One of the footage in the video shows the three royal children playing in Kate's "Back to Nature" garden at the Chelsea Flower Show last summer. The words "Find Your Brave," the theme of this year's Children's Mental Health Week, flash in between the footage. The initiative aims to encourage young people to share their mental struggles and highlight to them that being brave does not mean coping alone with mental health concerns.

Children's Mental Health Week was first launched by the charity Place2Be in 2015, with support from the Duchess of Cambridge who has been the royal patron of the organisation since 2013. The trust provides mental health support in schools across the United Kingdom.

The duchess had released a statement on Monday to mark the start of the Mental Health Week. The statement shared by Kensington Palace read: "For many children today, the world can feel a scary and daunting place. While we might not always feel brave inside, even the smallest act—such as sharing a worry or asking for help—can be incredibly courageous. Helping children to feel confident about seeking support can have a transformational impact on their lives."

The 38-year-old further spoke about the importance of trying new things out of the comfort zone to help children build resilience and self-esteem to cope with adult challenges. "Learning these skills early in life can give children tools to cope with future challenges they may face in adulthood," Kate wrote.

In her statement, the mother-of-three also stressed the importance of her 5 Big Questions survey, a part of her ongoing initiative to support the early development of children. "Our long-term ambition is to bring about positive, lasting change for generations to come," the royal said.