Prince Harry will find the Coronation service "doubles down" on his pain of being the spare, a royal expert has claimed.
In the next few days, Harry will be preparing to jet into the UK to be at Westminster Abbey on Saturday to see his father King Charles crowned.
He will be making the trip to his home country solo as wife Meghan Markle is remaining at their California home with their children Prince Archie and Princess Lilibet.
It will be the first time Harry has been in a public setting with his royal relatives since he criticised many of them in his memoir, Spare, which was published in January.
The book went into detail about how difficult he found being the second-born son behind Prince William - including claims that William physically attacked him and that the King put his own interests above his.
And according to royal expert and historian Dr Tessa Dunlop, this means it will take a fair amount of courage for Harry to be in the Abbey on Saturday.
She told the Mirror: "Yes, I think it will take guts for the Duke of Sussex to walk into Westminster Abbey alone on Saturday.
"But if we've learnt anything about Harry over the last few years it's that he doesn't shy away from a challenge. He's addicted to the rush of adrenalin.
"Early on, the prince made a name for himself as a royal hell raiser, flying Apace helicopters, trekking towards the North Pole and trialling psychedelic drugs.
"Now, although professing to long for the quiet life, (or at least a different life) he has published his own narrative in book and Netflix form, both of which were designed to court controversy.
"Detonating verbal bombs against the institution of monarchy and the British press is not a hobby for the faint-hearted. Nor is facing down several massive publishing companies in court…
"But no matter how gutsy he is, and despite a lifetime of training in the public eye, Saturday will be a massive challenge for Prince Harry."
Tessa added that she thinks Harry's solo visit will make it harder for him - and the day will no doubt bring back painful memories, especially as William and his nephew Prince George have prominent roles in the service.
She explained: " Going solo into that abbey, under the gaze of a thousand lenses, exchanging pleasantries with people he is no longer speaking to, that's a very tough gig for any man.
"And one made emotionally harder because the entire Coronation ceremony is about affirming and reaffirming the line of succession.
"It took the abdicated Edward VIII several hours before he telephoned a congratulatory message to his newly crowned brother George VI in 1937. Sibling rivalries run deep.
"Saturday is King Charles' big day, and in second place comes Harry's brother William, the Prince of Wales and heir to the throne, and then his nine-year-old nephew, Prince George, one of eight honorary pageboys.
The Coronation service will double down on the painful fact that Harry is and always has been, the spare.
"Amidst pomp and ceremony he is no longer part of, sitting several rows back and stripped of his military uniform, Harry won't find the service easy.
"A long way from his new Californian home, emotionally he'll be reminded of just how far he has travelled from his old one. In Harry's Netflix series, he admitted missing big eccentric dinners in palaces, however, I suspect Saturday will bring him no nearer to returning to the royal fold.
"Harry probably knows this and as he readies to leave his sun-drenched Californian life, packing his case and civilian suit for the big day, I expect he will be feeling wistful and a little worried.
"King Charles and Princes William and George are protected by Britain's ancient institution of state, monarchy. They will have clearly defined roles and costumes on Saturday. Not so Harry, who has opted for life on the outside. History tells us that is never an easy path for an ex-royal."
Tessa Dunlop is the author of Elizabeth & Philip, the story of young love, marriage and monarchy, published by Headline Press and now out in updated paperback.
