Prince William has encouraged people to be "open and honest" about their mental health.
Prince William and the Duchess
The 34-year-old royal campaigns on behalf of the mental health charity Heads Together and in an impassioned speech, Prince William has stressed the importance of being candid about such issues.
He said: "Mental health matters to each and every one of us. It matters just as much as our physical health.
"The crews I have worked with, whether RAF Search and Rescue or Air Ambulance, must take their mental health as seriously as they do their physical health or else they would not cope - and, actually, that is true for everybody at some time or another in their life.
"There are times when, whoever we are, it is hard to cope with challenges - and when that happens being open and honest and asking for help is life-changing."
The Prince was joined at the Heads Together event by his wife, the Duchess of Cambridge, and his brother Prince Harry.
The Duchess is a reluctant public speaker, but she too stressed the need to be honest about mental health issues.
She said: "William, Harry and I have been very privileged to witness in the course of our work countless examples of simple conversations that have changed lives, which were the first step on a path to recovery.
"Just last week at the Anna Freud Centre, I heard from one mother how talking to a support worker was - in her words - like medicine."
The Duchess said having someone to confide in can be a huge benefit if you are suffering with mental health issues.
The 35-year-old royal explained: "Simply by having someone there to have a conversation with helped her immensely."
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