Kate Middleton's 'secret code' with children at public events

Kate Middleton and Prince William are known to be hands-on parents to their three children

The Duchess of Cambridge reportedly employs a 'secret code' to manage the behaviour of her children, Prince George, Princess Charlotte and Prince Louis. The young royals, known for their playful public personas, have occasionally displayed their cheeky sides during public appearances.

And when Kate feels their behaviour is crossing a line, she will use a 'code' to issue a warning. Royal expert Tom Quinn revealed all in his book Gilded Youth, An Intimate History of Growing Up in the Royal Family. He wrote: "When Prince Louis misbehaved at the late Queen's Platinum Jubilee for example, by sticking his tongue out at his mother, Kate's reaction was praised by a team of expert commentators.

"She apparently used a secret code to calm the children, as she does on occasions - she simply says 'let's take a break'. But as a former staffer explained, the children know these few words carry far more weight than we might imagine." For the latest Welsh news delivered to your inbox sign up to our newsletter

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At Adelaide Cottage, home to Prince William and Kate Middleton's family, stringent rules are in place for their children Prince George, Princess Charlotte, and Prince Louis. Should any of the young royals struggle with their emotions or outbursts, the Duke and Duchess opt for 'sofa chats' rather than isolation, providing guidance and support to the child in understanding the situation.

Furthermore, a strict 'no shouting' policy is enforced. Any child who raises their voice is removed from the scenario, and similarly, the Duke and Duchess refrain from raising their voices when disciplining George, Charlotte, and Louis, reports the Mirror.

An insider previously told the Sun that Kate is "slightly stricter" than Prince William, adding that the royal couple's nanny, Maria Teresa Turrion Borrallo, makes all decisions in agreement with the couple.

The insider said: "Maria is firm but she never acts unilaterally with the children on discipline. Kate and William, along with Maria, are strict with the children but have this magic ability to appear not to be. It is a military operation but you would never guess it because they work ferociously hard on their children's upbringing and making it seem relaxed and happy for the three of them. They are very good at listening to the children but being firm."

Royal expert Victoria Murphy shared insights with ABC News back in May 2015, saying: "The nannies are taught everything from defensive driving to security issues to how to care for a future king or queen," and added, "So [Borrallo] just really knows everything that you could possibly need to know about bringing up a child."