The Princess of Wales has made what's been called her biggest speech yet on the issue she is most passionate about: early childhood.
Kate brought together world experts in the field of child development and also a former UK prime minister as she spoke about how she wants to help the most vulnerable children and adults in our society.
The princess said: "I care deeply about making a positive difference, in helping the most vulnerable and supporting those who are most in need."
She has focussed a lot of her recent work on the study of children from birth to age five and said "long term, preventative change" in adults means we should go "back to the beginning".
Kate launched her "Shaping Us" campaign earlier this year as part of her Royal Foundation Centre for Early Childhood.
She believes that a healthy, confident adult with good physical and mental health has his or her foundations in the earliest years of life. She told a conference on Early Years at the Design Museum in London that we should care about child development as much as we should care about the health of our planet.
The princess said: "Just as we need to restore, protect, and invest in our planet, so we must restore, protect, and invest in our societies, communities, relationships, and ourselves."
Just as her husband, Prince William, invests a lot of energy and time in his ten-year Earthshot Prize initiative, Kate is focussed on the time which she called "the golden opportunity to establish the core foundations and capabilities we need to thrive all the way through our lives."
Scientists and child development experts say that the time between pregnancy and age five, is when the brain is at its most receptive and develops faster than any other time in our lives.
"If we don’t put these building blocks in place when we’re young, we find it much harder to manage ourselves, communicate and connect to others and engage with the world around us in adulthood," Kate said in her speech.
Before her speech, Kate chatted about how her youngest son, Prince Louis, is encouraged to express his feelings at his school.
The Princess said Louis has a colour wheel in his class and he goes in “with names or pictures of a colour that represents how they feel that day, so there is a real keenness in school particularly to get involved in conversations”.
Former prime minister Tony Blair was asked to join the Princess of Wales’ gathering today to speak about how politicians can create change.
Sir Tony, who was prime minister from 1997 to 2007 set up Labour’s Sure Start scheme to give parents better childcare options.
Speaking at the conference alongside William Hague, Sir Tony said: "I really think this subject, about how you shape the early years, is phenomenally important today.
"That early education, however they get it, is so critical to their development and if they don’t get it, they are always playing catch up. I think now that we know that the evidence is there, the rest of it’s just political will and policy.
"I think you need to get policy in this area that’s really imaginative. I don’t think there should be any great political divide about the importance of early years. I think wherever you sit in the political spectrum, we should accept it and people do.
"The question is, what’s the best way of getting the right policy in place that this can be a reality."
The pair also spoke about the importance of developing “emotional resilience” in childhood.
Sir Tony said: "There was a time in my life when I really did want to be a rock star. I was in a band with very long hair and I was the singer in the band and occasionally played the guitar.”
He said he’d had a conversation with the lead guitarist who told him: "I really like you but frankly you’re useless. You can’t sing and you’re not very good at the guitar so you’re going to have to find something else."
Lord Hague replied that it “would have been great” if Sir Tony had become a rock star as he’d have had “an easier career”.
But Kensington Palace is acutely aware that Kate’s work in this area cannot stray into the political arena.
A royal source acknowledged the “policy lever” is not one the princess can pull but she does have access to other levers - like being a convener - so, like today, she can bring the world’s experts in this field together with politicians and decision makers.
The princess' Shaping Us campaign is starting to work with some big employers to change the way they treat staff from the moment they become pregnant to the time when their children are in the most important developmental stage.
The financial services company Aviva, retailers Iceland, Coop and IKEA and the banking giant NatWest are all part of the campaign to change the way businesses look after their staff.
The conference heard how these kinds of changes can have a huge impact on the welfare of children and their parents.
Kate’s campaign has expanded from a UK-based one to a global initiative after conducting research in 21 different countries to find the common threads that apply to all children and adults no matter where they grow up in the world.
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