Their appearance was as relaxed as the royal couple themselves.

Dressed in casual clothes, Kate Middleton and Prince William visited Harrow College in London on Oct. 10 to raise awareness for World Mental Health Day. The couple met with children and teens who have battled mental health problems and listened with concern as the young participants opened up about their experiences.

kate middleton and princess charlotte

Kate and Charlotte in July 2015.

“Kate and William are very focused on charities that benefit children now that they have a growing family,” a royals insider tells Closer. “This is a cause that’s very close to their hearts.”

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While they’re dedicated to addressing important issues, Kate and William, both 33, are also fiercely determined to ensure that their own children — Prince George, 2, and Princess Charlotte, 5 months — come first. And if that means bucking protocol, so be it.

prince william and prince george

William and George in July 2015.

“Kate and William have broken the mold when it comes to putting family before royal duties,” says the insider. A thoroughly modern couple, they split parenting duties and work at creating as nurturing a household as possible.

“What Kate and William want is a normal life for George and Charlotte,” adds the insider. “They want their children to grow up with shared parenting rather than the old-fashioned royal way of having nannies raising the children.”

To read the full story on Kate and William, pick up the new issue of Closer Weekly, on newsstands now!