Prince Harry has spoken of the grief and trauma he went through as a young boy following the death of his mother Princess Diana.
MORE: Prince William and Kate share sweet family photo in honour of Queen's 96th birthday
The Duke of Sussex, who is the chief impact officer for professional coaching and mental health firm BetterUp, shared his desire to drive further "advocacy and awareness for mental fitness", and called on everyone to focus on being "proactive".
WATCH: Prince Harry says Princess Diana 'smashed the wall down' around HIV stigma
"Ninety-nine point nine percent of people on planet Earth are suffering from some form of loss, trauma or grief," he said.
"It doesn’t matter what age you are, but the majority of us have experienced a lot of that in our younger years, therefore we’ve forgotten about it.
MORE: Prince Harry enjoys secret outing to Irish pub – check out his order
READ: Prince Harry and Prince William celebrate baby joy with close friends
"Now, the body doesn’t forget, the body holds the score as we know. And, therefore, just as much as there’s a mental health aspect to it, there’s also the emotional aspect to it as well."
Diana tragically passed away after being injured in a car crash in Paris on 31 August, 1997. Harry was 13 at the time.
A young Harry with his mother Princess Diana
Speaking on the The Masters of Scale podcast, which interviews start-up entrepreneurs about the key to their success, and is hosted by LinkedIn co-founder Reid Hoffman, Harry continued: "Rather than looking at going, ‘Yeah, exactly that, every single day I’m trying to survive’ or, ‘Every single day I’m trying to cope’, I think we need to completely change it."
He continued: "And that’s what I mean about the difference between mental health and mental fitness. The mental fitness aspect is like, ‘I’m not going to wait for myself to be, either collapse on the floor or wait to have a nervous breakdown or burnout and then have to fall on my friends or then have to pay X amount of money or find the money to be able to afford professional help’.
"Mental fitness, as far as I understand it, is more a case of getting on the front foot. What can you do to be proactive, to prevent the situation from happening?"
Harry was 13 when she died
San Francisco-based BetterUp is valued at more than a billion dollars and Harry’s role, which he took on in March last year, includes product strategy, philanthropy and public advocacy related to mental health.
He is also involved in the firm’s commitment to Pledge 1% – a movement which encourages companies to donate 1% of equity, staff time, product or profit to their communities.
Harry recently shared that his two children call their late grandother Grandma Diana, and that he feels her presence constantly.
Harry is now married with two children
"It has been over the last two years more so than ever before," he said.
"It is almost as though she's done her bit with my brother and now she's very much like helping me. She got him set up and now she's helping me set up. That's what it feels like. He's got his kids, I've got my kids."
He added: "She's watching over us."
