On Wednesday (Feb. 13), the Duchess of Cambridge gave an impassioned and moving speech about something that is near and dear to her heart: mental health. On behalf of the Fab Four – which includes Prince William, Prince Harryand Duchess Meghan – the mother of three attended the Royal Foundation's "Mental Health in Education" conference. The event brought together delegates from across mental health and education sectors to explore and discuss the benefits of collaborative working.

Mental health is a very important cause to Kate. Photo: © Chris Jackson - WPA Pool/Getty Images

“Over the last eight years working with charities, I’ve met some of our leading experts in mental health, addiction, family breakdown, homelessness and education," the duchess said to the crowd. “They have taught me over and over again that the root cause of so many of today’s social problems can be traced right back to the very earliest years of a person’s life and often over generations.”

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She added: “The scientific and other evidence is clear: the first few years of a child’s life are more pivotal for development and for future health and happiness than any other single moment in our lifetime. No one of us, however, can make a difference alone. I feel so passionately about working together and being here today has affirmed to me just how much already is being done, so thank you to all of you who are prioritizing the importance of mental health and the importance of childhood development as a whole.”

She concluded the speech by saying: “I look forward to hearing how your discussions will lead to proactive steps and to an ever more resounding commitment to mentally healthy schools, teachers and children.”

As a patron of Place2Be, the Duchess of Cambridge has made it her mission to reduce stigma surrounding mental health, and help families and children access the support they need. She also started Head's Together – a Royal Foundation project for mental health – with Princes William and Harry.

Last year at around this time, Kate marked the start of Children's Mental Health Week with yet another impassioned speech encouraging children to open up about their emotions. "Childhood is an incredibly important moment in our lives," she said. "It is the time when we explore our personalities, discover the potential that lies within us and learn how to be ourselves. Our experience of the world at this early stage helps to shape who we become as adults, how we begin to feel comfortable in our own skin."

She then asked that adults help guide youth in their mental health journey, saying: "Some children will be facing tougher challenges than others, but I firmly believe that while we cannot change their circumstances, we can ensure that every child is given the best possible support to ensure they fulfill their true potential. This is best achieved when we, the adults in their lives, work together to give children the emotional strength they need to face their futures and thrive."