Unlike his sisters, James Middleton has stayed (relatively) away from the public eye.
But in a heartbreakingly honest article, the younger brother of Duchess Catherine and Pippa Matthews has opened up about his personal struggle with depression and his eventual diagnosis with Attention Deficit Disorder (ADD).
In the article, written for the Daily Mail, James spoke candidly about how his formerly monotonous routine and how he "sank progressively deeper into a morass of despair."
"I know I'm richly blessed and live a privileged life," he penned.
"But it did not make me immune to depression. It is tricky to describe the condition. It is not merely sadness. It is an illness, a cancer of the mind."
The youngest Middleton has decided to open up firstly because he has come to terms with his mental illness and has worked out his own coping strategies and secondly to help change the negative stigma that surrounds mental health.
James also wanted to speak out to support the work that his royal sister Duchess Catherine, along with Prince William and Prince Harry, have advocated since establishing their mental health charity, Heads Together.
James, 31, confessed that he has suffered with severe dyslexia since his childhood, and even today he struggles with spelling and numbers. In fact, when he was asked to read out loud in class, the letters would "jump around" and he'd read a different story to everyone else.
"I was terrified of ridicule and ashamed of being a slow learner. I hid my beginner's reading book inside a more advanced one so none of my classmates knew I was so far behind them."
James's dyslexia also affected him socially as he'd miss out on extracurricular activities to catch up on his school work.
But despite being very slow with his academic work, James says that he was "dextrous and practical" and his curiosity fuelled him to take things apart and re-build them.
"I assembled IKEA flat packs without the instructions, intuiting exactly how the pieces fitted together, just from a drawing of the finished product," he wrote.
Things didn't improve as James entered the senior school at Marlborough College.
"[Duchess] Catherine had already left for university by the time I got there, but having Pippa around was a comfort. Even so, I didn't fit in."
Eventually, James made it through his high school exams and secured a place at Edinburgh University like big sister Pippa, but after a year he quit.
"I'm not criticising the system. But because I didn't know my brain worked differently — and neither did my parents — I couldn't find a way of steering round my ADD. If diagnosis and help had happened sooner, I'd have found life so much easier."
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At the end of 2016, James learned from his doctor that his irregular heartbeat was brought on by stress and anxiety. Despite his doctor's advice though, he treated his symptoms with short-term medication but refused to look into the root of the problem.
"The best part of 2017 passed in a fog. I barely functioned, stopped talking to my friends, went through the motions of living and working but achieved nothing at all."
After a year of torment, James finally decided to visit his doctor again.
"When I rang her I felt as if I was trying to hold in a waterfall of emotion. I struggled to get the words out and I was close to sobbing," he confessed.
But it wasn't until December 2017 when he finally started to see some progress. The young businessman packed up his dogs and escaped to a remote cottage in the Lake District without telling anyone to try and calm his mind.
"In the days before, I'd finally confronted the fact that I couldn't cope any longer, that I wasn't all right; that I desperately needed help. And this recognition led to a sort of calm: I knew if I accepted help there would be hope. It was a tiny spark of light in the darkness."
Thankfully, James has been seeing a psychiatrist for weekly appointments to understand coping techniques for his depression. It was there that he was also diagnosed with ADD, which he joked was the only test he'd ever passed first time!
James says he has also learned to accept the support from his loved ones, particularly his family.
"If I could leave you with just one thought, it would be this: 'It's OK not to be OK,'" he concluded his article.
"That is the mantra that gave me the strength to speak out. Having done so here, it feels as if a great weight has been lifted."
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