Prince William "took a lot home" when he worked as an air ambulance pilot.
Prince William
The 36-year-old royal worked for the East Anglian Air Ambulance as a first responder for two years and admits it was tough seeing such "despair and sadness".
Speaking at a mental health event in Bristol, he said: "I took a lot home without realising it. You see so many sad things every day that you think life is like that.
"You're always dealing with despair and sadness and injury. The attrition builds up and you never really have the opportunity to offload anything if you're not careful."
Meanwhile, William - who has Prince George, five, Princess Charlotte, three, and Prince Louis, four months, with his wife Duchess Catherine - announced in January 2017 that he would be stepping down from the job and said it was a "huge privilege" to work with the East Anglia Air Ambulance.
He said in a statement at the time: "It has been a huge privilege to fly with the East Anglia Air Ambulance. Following on from my time in the military, I have had experiences in this job I will carry with me for the rest of my life, and that will add a valuable perspective to my royal work for decades to come. I would like to thank the people of East Anglia for being so supportive of my role and for letting me get on with the job when they have seen me in the community or at our region's hospitals.
"I would especially like to thank all of my colleagues at EAAA, Babcock and Cambridge Airport for their friendship and support. I have loved being part of a team of professional, talented people that save lives every day. My admiration for our country's medical and emergency services community could not be any stronger."
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