The royals release serious message in candy-sweet packaging.

The Duke and Duchess of Cambridge and Prince Harry have swapped their crowns for sweatbands and they’re not ashamed to talk about it.

The three young icons of the royal family have appeared in a video to launch an initiative that aims to remove the stigma attached to mental health.

The Heads Together campaign wants to change Britain’s conversation surrounding mental illness to ensure better outcomes for individuals.

The video released on Sunday is already receiving great traction for its important message wrapped in a candidly sweet clip.

Appearing in a close-cropped shot, Duchess Kate Middleton speaks passionately about the topic.

"Mental health is just as important as physical health," the Duchess said.

Prince Harry continues by discussing how important it is to normalise conversations around mental well-being.

"We can all play our parts by talking and listening to each other," Prince Harry said.

The Duke of Cambridge then brought it home.

"Let's get our heads together and change the conversation on mental health," Prince William said.

A spokesperson for Kensington Palace said in a statement it was the "biggest single project Their Royal Highnesses have undertaken together."

The highlight of the clip is at the end when the Duke and Duchess of Cambridge stand arm-in-arm with Prince Harry, attempting to take a 'serious photo' for publicity.

"Do a serious one?" Prince Harry suggests.

"A serious one." Prince William echoes.

The result is a painfully cute amount of suppressed giggles before all three give in to laughter.