The Duke of Cambridge plans to train as a volunteer counsellor for the text crisis service Shout, he revealed on Monday. William spoke of his ambition as Shout announced a partnership with emergency services organisations that will connect "bluelight" staff and their families to the support they need.
Chatting to volunteers from the service, which was developed by the Royal Foundation, he said: "I'm aiming to set myself up for it, I really want to do it. Even if I can only do an hour on my laptop. I want to do the training and be able to help."
Members of the emergency services community can text BLUELIGHT to 85258 to start a conversation with a trained volunteer at Shout, which was developed with the Royal Foundation as a legacy of the Heads Together Campaign.
On a visit to mark Emergency Services Day, the Duke was speaking to emergency responders at Harcombe House in Devon, one of three UK residential centres run by The Fire Fighters' Charity.
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During an art therapy session at the centre, which has just undergone a £1.8million refurbishment, William met retired firefighter Richard Baldwin, 70, and his wife Susan, and serving firefighter Dan Bills, his wife Kelly and their three children.
The Duke, a former air ambulance and search and rescue pilot said: "What I always find with the blue light community is that you put the hat and the uniform on day in day out and you see whole families being torn apart."
"You try and compartmentalise, you try not to bring it back to your own family but after a while one or two jobs catch up with you.
"If the blue light community can be more open about the things that bother them, then others can as well. "We are not robots and, if you are in the emergency services for long enough, you see really distressing things. All that weighs upon you, and if you have something going on at home - family, illness - it all gets on top of you, too many things to keep a lid on."
Asking Richard about the job he began in 1968, William said: "Mental health wasn't a thing, was it?"
Dan 35, from the London Fire Service, said: "It's changed in the last 10 years. If you went to an incident that was difficult it was barely spoken about.
"People don't hesitate now, there's no shame now."
As he admired artwork by Dan's children Joshua, 12, Mia, seven and and three-year-old Isla, the Duke spotted a unicorn horn made from colourful balls.
"My daughter loves unicorns," he said. "Loves them. Very cool."
Four-year-old Princess Charlotte was spotted on her first day at school last week with a sparkly unicorn head bag charm on her bookbag. She was also seen carrying a unicorn purse at the polo in July.
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Speaking afterwards Dan said: "He was such a pleasant, down to earth, humble guy who made you feel comfortable. You could see he had a genuine interest in what we had experienced."
Dan and his family have visited the centre for the past eight years after struggling with son Joshua's autism diagnosis.
Richard, 70, of Tiverton, suffers from PTSD after serving for two decades in the Berkshire Fire Service and also uses a wheelchair after having both legs amputated due to illness.
After meeting the Duke he said: "You can tell he's a family man, he's a natural. What a gentleman. I never thought I would have to show the future King of England my legs!"
"If you don't speak out, nobody is going to know. The things you see, the things you do. They do a fabulous job here."
In the gym the Duke spoke to users including John Couzins, 66, who was exercising on anti-gravity treadmill as part of his recovery from knee surgery.
"It's really good to have him here with what's going on at the moment. We have still got a royal family doing their bit and trying to understand what's going on with the ordinary person.
He said of the centre: "It has been fantastic, it's a new lease of life, physically and psychologically."
The Duke's interest in mental health has been influenced by his two-year role as a helicopter pilot for the East Anglian Air Ambulance, which ended in July 2017.
He previously served for nearly five years as a helicopter pilot with the RAF's Search and Rescue Force.
Last week he backed plans for a National Emergency Services Memorial to honour the more than 7,000 people who have died while service in police, fire, coastguard and search and rescue services.
He said: "As a society, we owe our wellbeing, and indeed our lives, to the men and women in our emergency services who work tirelessly to protect us in some of the most difficult circumstances.
"It is only fitting that we should recognise the vital role that they play, and pay tribute to the bravery and dedication of those who have made the ultimate sacrifice for their communities."