It's a key milestone in anyone's life and as she celebrates her 40th birthday this week, the Duchess of Cambridge is entering her prime. Settled and fulfilled in her roles of wife and mother, she has carved out a progressive role for herself as a senior working member of the royal family.
As she enters her fifth decade, HELLO! has spoken to some of those who know Kate best, from royal insiders and friends to charity representatives. They reveal how Kate is a "natural introvert" who has overcome her shyness to use her platform for good, but is "very self-deprecating and funny too".
WATCH: Kate Middleton's milestones as she celebrates 40th birthday
They describe how the Duchess is motivated by the long-term impact of her work, focusing on "decades, not years, not months, not quarterly cycles". And they reveal how she spontaneously attended the vigil for Sarah Everard because "she felt it was really important to be part of the moment," only telling Palace staff about it afterwards.
The real Kate: 'She would never have sought a public role'
After a decade in public life, Kate has not only embraced her official duties and patronages, but gone a step further in making a focus on the Early Years her life's work. And when she sat down at the grand piano to accompany Tom Walker at the Abbey last month, she looked every inch the polished public performer.
For those who know her well, it was a moment that was years in the making. "She's had a remarkable year, built on years and years of planning," a royal insider tells HELLO! "She's taken her time and really done things in her own way. I think she would say herself that she wasn't born to be a public figure. She's a reserved person and she's incredibly thoughtful, but she would never have sought a public role if it hadn't been for the man that she married."
Overcoming her nervousness around public speaking
When it comes to public speaking, "It's not something that she relishes doing, at all," says the insider. "She's not a put yourself out there, extroverted type of person, it's just not who she is. But she knows it's an important way for her to make a positive contribution and there are some times that you need to get out there and speak for things you believe in."
"She's not a put yourself out there, extroverted type of person, it's just not who she is," said an insider
Royal watchers have also observed a greater willingness to use her voice and how she has overcome her nervousness around public speaking without any formal training. "She works really hard to make sure the words are her words and really prepares," says the insider. "So when people hear her speaking it's genuinely what she believes. What you see is what you get."
So when her husband Prince William asked her to present one of his Earthshot Awards back in September, Kate immediately said yes. "It was a big television moment, millions of viewers and everyone else was a celebrity," says a friend. "A few years ago, that would have been a much more stressful thing for her. But because she has taken risks and put herself out there on other things she's cared about and she's seen that she can do it, she's just much more confident.
"Of course she had nerves on the day. But people respect that and like [the fact] that she's not flashy and you're seeing an authentic person trying to do good work."
Backstage with Emma Thompson at the Earthshot Awards
Nowhere has the change in her been more apparent than at East Anglia's Children's Hospices, where she gave her first speech as patron as she opened The Treehouse in Ipswich in 2012.
"Although confident from the start, it's clear she has grown into public speaking and meeting staff and families very quickly," says EACH spokesman Simon Hempsall. "In 2019, her speech at the opening of our hospice in Norfolk, The Nook, was exceptional." He said of the Duchess, who has made many private visits to support the charity, "She has shown enormous empathy and understanding when meeting children and families. Everyone reacts so positively to her and appreciates the generous and very personal time she spends with them."
Relatable and caring Kate
In recent years, Kate has been more relaxed and open in talking about her own family life – speaking for millions of exhausted parents when she shared the challenges of homeschooling her three children during lockdown. And another example from the past year stands out as a reminder of Kate's very normal life prior to her marriage into the royal family.
Amid an outpouring of grief and protest following the murder of a young woman, Sarah Everard, by a serving police officer, the Duchess quietly attended a vigil to lay flowers in her memory and later wrote to Sarah's family to express her sadness. At the time, a source told HELLO! "She remembers what it felt like to walk around London at night."
Her caring nature has been clear to see over the years
It was a hugely relatable moment for young women around the country and Kate felt compelled to show unity with them, only discussing it with her protection officers beforehand.
"She just acted," a friend told HELLO! "She felt it was really important to be part of the moment because she felt really emotional about it herself." It was a rare public display of spontaneity from the Duchess, whose approach to her public life is always very considered.
"She's got a really long-term view," a source who has worked with the Duchess tells HELLO! "She thinks of her projects and her role within the institution and looks at everything through a 20 to 30-year lens. She's naturally strategic. And her ambition is to have real impact on society."
A future Queen in the making but she's 'very self-deprecating and funny too'
Meanwhile, her stature on the world stage has grown. Whether she is entertaining world leaders at Buckingham Palace or visiting a school with First Lady Jill Biden, she is very much a future Queen in the making. "Hers is an understated presence," says the source. "But she's quietly growing in confidence. She still finds it quite challenging to mix with those sorts of players, because she's a natural introvert. But she's really growing into the role."
With experience, Kate has become more confident to lead on projects, creating both the poignant televised carol service and Hold Still, a photography competition which became a book and a nationwide exhibition.
"She's a natural introvert. But she's really growing into the role," said an insider
"All of it was her," says the insider. "She's got a very creative mind and she goes into meetings with those ideas fully formed. She's all over all the detail and very much part of the team. It's really exciting working with someone like that. It's not what you expect from a future Queen.
"She's very focused - she always arrives with loads of notes and ideas and articles that she's seen, but she's very self-deprecating and funny too. She's had a bit more time in the last couple of years with the kids getting a bit older. She gets a lot out of it."
Kate's genuine commitment: 'It wasn't a photo op'
Another organisation to benefit from Kate's long-term focus is the Scout Association, with Chief Scout Bear Grylls telling HELLO!: "The Duchess is loved and admired for her passion for early years youth work and it has been amazing seeing her give so much time and energy to Scouts across the country for many years.
"We are so proud to have her as a joint President and when she wears her Scout scarf she shows her solidarity with 57 million young people worldwide who know the power of Scouting to change & improve their lives. To me she is a hero."
Kate has even trained as a scout volunteer, with a Scouts source saying: "Our people love that. They feel like she's one of them."
After an engagement making vegetarian burgers with the Scouts at Cop26 in November, she waited for the media to leave before going back inside to eat with them. The source adds: "It wasn't a photo op that was just for the moment, and that's really important because you know then it's not a lip service issue, it's a belief in the values of the organisation."
"They feel like she's one of them," said a Scouts source
Kate's very personal approach has seen her befriend Holocaust survivors, including Yvonne Bernstein and Stephen Frank, whose portraits by the Duchess appear in the Imperial War Museum exhibition Generations: Portrait of Holocaust Survivors until January 9.
"She didn't just want to meet the survivors and take their photos, she wanted to hear their experiences and get to know them," says Olivia-Marks-Woldman, chief executive of the Holocaust Memorial Day Trust.
"She's written to them, sent them Christmas cards, invited them to other events. She's displayed such empathy and warmth to them and their families. And on the strength of that she's wanted to tell her own family about the Holocaust, in an appropriate way, because they are very young. What an example that sets for other parents. It really challenges that prejudice that other people might have. It's immensely powerful."
Grateful for the opportunity to make a difference
The royal insider explains how Kate's increased focus on her work comes from years of preparation, saying: "She's really grateful for the opportunity she has to make a difference but she's had to take her time in charting her own path. She didn't rush for any short-term wins in those early years. She's just not motivated by that.
"She's not interested in day-to-day press coverage. She is very focused on the long term. She knows that her role is to be able to support William and the institution and her family for the long term. Decades, not years, not months, not quarterly cycles."
Kate's power to bring people together
Kate set out after her marriage to really understand some of the issues that she was encountering on engagements around families and relationships, addiction and mental health.
Her work has led her to passionately believe in giving all children the best possible start in life and in June she launched the Royal Foundation Centre for Early Childhood, which brings together experts to collaborate on solving family problems that can lead to issues such as addiction, homelessness and domestic violence in later life.
"She realised through her work in those areas, that it all stems from those formative years and whether they were good or not," explains a royal source. "This is the culmination of her ten-year career as a working royal that has led her to a space where she can use her role, her power of bringing people together to find solutions."
The Duchess has the power to bring people together to find solutions
In June, the Centre published its first report, Big Change Starts Small, after Kate "went over it with a fine-tooth comb and debated it with the scientists," adds the source.
"She doesn't have to do this, but she does. And it shows how much it means to her," says Dr Guddi Singh, a consultant in neurodevelopment and social paediatrics, who discussed the findings with the Duchess. "She's thought about how she can use her role to bring about significant and lasting change. Not everybody who has power does that."
As Kate herself told experts gathered for the Royal Foundation's forum on the Early Years in November: "It is a brave thing to believe in an outcome - in a world even - that might not be fully felt for a generation or more. But what you do isn't for the quick win - it is for the big win. It is for a happier, healthier society as well as happier, healthier children."
Dr Guddi adds: "To bring all those people together, you've got to be a special kind of person. She can get people together. That's her power. The thing that makes the Duchess different to any politician is that she doesn't have the short-term cycle. She's not looking for your vote, she doesn't have to react to what's trendy.
"She knows that it won't happen overnight, but it's about putting into place things that will help kids in the future. It's that kind of thinking that is a game-changer. I'm so glad she's on our side. I think her impact in this space is huge."
The Early Years is a "lifelong commitment" for the mother-of-three
"It's a lifelong commitment," says Jason Knauf, outgoing chief executive of the Royal Foundation of the Duke and Duchess of Cambridge. "She thinks that this issue is the social equivalent of climate change and that it needs to be considered as just as serious. What we're not discussing with the seriousness it deserves is just how powerful brain science now is. She believes that if that science becomes famous in the same way that climate science has become famous, it could have a hugely positive effect across every aspect of society."
A royal source adds: "These aren't things that she will ever lobby for directly – her role is to raise awareness and the rest will follow."
'A thoroughly decent human being' who wants to improve lives
Professor Peter Fonagy, chief executive of the Anna Freud Centre for Children and Families believes the Duchess's work is paying off, telling HELLO! "She's made the topic of parenting, of looking after little babies and small children, something of importance.
"She's quite a remarkable individual. It's the clarity of vision and the way she immerses herself in the work and then communicates her understanding that makes her a really quite formidable force. And she has done a great deal off camera."
Peter, who has worked with the Duchess since 2015, adds: "For someone in her position, she was always unusual in the amount of subject matter expertise that she has, and that has deepened and broadened in the time that I've known her, but she always talks with humility.
"She would make a great clinical psychologist. I've seen her on many occasions talking to quite difficult children, kids who have been excluded from school, but she talks to them in a way that is really quite exceptional. She's a thoroughly decent human being. Someone with genuine concern and wanting to make use in the best way she can, the most serious and committed way she can, of her current position, to improve lives."
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