Kate said making Prince George, the future King, and his sister Princess Charlotte aware of the value of these qualities was just as important as academic or sporting success.
The Duchess’s revealing comments came as she celebrated pupils with the “K factor”, or kindness factor, during a visit to Mitchell Brook Primary in north-west London with her husband the Duke for the launch of Children’s Mental Health Week.
The annual event – which this year has the theme Spread A Little Kindness – is an initiative founded by the mental health charity Place2Be, which has Kate as royal patron, and runs counselling sessions at Mitchell Brook in Neasden.
The Duke and Duchess of Cambridge marked the start of Children's Mental Health Week
The 35-year-old Duchess, who wore an outfit by the Italian designer Luisa Spagnoli, said: “My parents taught me about the importance of qualities like kindness, respect, and honesty, and I realise how central values like these have been to me throughout my life.
“That is why William and I want to teach our little children George and Charlotte just how important these things are as they grow up.
“In my view it is just as important as excelling at maths or sport.”
Speaking during a special school assembly where those with the K factor were recognised, the Duchess added: “People often ask me why I am so interested in the mental health of children and young people.
“The answer is quite simple – it is because I think that every child should have the best possible start in life.
“When I was growing up I was very lucky. My family was the most important thing to me.
“They provided me with somewhere safe to grow and learn, and I know I was fortunate not to have been confronted by serious adversity at a young age.”
The Royal couple spearhead the Heads Together campaign
Today's engagement was part of a series of events the Duke and Duchess are undertaking – many with Prince Harry – to promote the royal trio’s Heads Together mental health campaign.
And it saw the Duchess back to her elegant best.
Just a day earlier she had been seen in trainers and puffa jacket for a charity marathon training event.
But accompanied by her husband William, Kate looked stunning in her favourite red suit.
One onlooker said: “The crowd went wild and the kids just loved her. From the smiles, she and William seemed to be very relaxed and enjoying the visit.”
Kate and William will attend a conference focusing on mental health
Kate, Duchess of Cambridge in pictures
Mon, February 6, 2017
Kate Middleton, Duchess of Cambridge, life in pictures; including royal visits around the world and her most stunning outfits.
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The Duchess of Cambridge arrives at London Primary school
During the event, the Royal couple were pictured sitting down on a “kindness bench” as they celebrated the efforts of school children with the “K factor”.
William and Kate then joined the special school assembly at the event in north west London where the youngsters have been learning about the importance of Children’s Mental Health Week which started on Monday.
The week has the theme Spread A Little Kindness and Nicola Harmer, the school’s deputy head teacher, said: “We’ve launched through a series of assemblies different people who have the K factor, the kindness factor, and then we’ve discussed with the children how they can have it.
“Whether it’s helping a friend out who feels a bit lonely on the day and supporting them, and we’ve also talked to the children about being kind to ourselves, that’s around the negative talk we may have of putting ourselves down.”
The kindness bench is normally in the school playground and sitting on it indicates the child is feeling lonely or in need of a friend and other pupils come forward to support them.
The royal couple sat on the bench which was placed on a stage in the school hall and watched the assembly that celebrated kindness.
Kate and William were serenaded by a small steel pan orchestra when they first arrived.
The Duchess is patron of the charity Place2Be which is behind Children’s Mental Health Week.
Place2Be is a children’s mental health charity and is part of Heads Together – an umbrella campaign spearheaded by the Duke and Duchess and Prince Harry.
It aims to change the national conversation on mental well-being to a positive one and is the charity of the year for the 2017 London Marathon.