The Duke of Sussex and Duke of Cambridge enjoyed a solid relationship in their earlier years, typified by the support they gave one another as they embarked on careers within the Armed Forces. Both would be on the phone with one another, and share their experiences – particularly Harry, who was said to have struggled to cope towards the end of his 10-year spell in the Army and his return to civilian life. Yet, the pair are deemed to have endured a bitter relationship in recent years, culminating in an alleged row regarding William’s “snobbishness” over Harry’s now-wife Meghan Markle.
This row was dissected within the controversial Finding Freedom biography, which followed Harry and Meghan’s final days within the Royal Family.
Author Robert Lacey, however, argued that this rift had actually come about many years before, as William began to understand his destiny as being an heir to the throne.
The writer of Battle of Brothers: William, Harry and the Inside Story of a Family in Tumult, believes it stemmed from Harry’s treatment after he infamously dressed up as a Nazi for a party.
The decision to wear such a contentious outfit was taken by both brothers, Mr Lacey claims, and left William “laughing all the way back to Highgrove” before Harry was snapped in the uniform.
The fallout was grim for Harry, as he made front page news across the globe and was fiercely criticised for bringing the UK, and the Royal Family, into disrepute.
Mr Lacey told Entertainment Tonight: “This is the first time we discover the conflict between the brothers, and Harry starts resenting this stereotype that is forced on him.
“William is the King of the castle, and he’s the dirty rascal. And when Kate comes along, he happily falls into the role of number three [in line to the throne] and it’s all so far so good.
“Then Harry falls in love with Meghan and that really turns things around, and she makes him see things in a new way so that’s where the rift really started with William and Harry. When he saw how deep he was falling in love with Meghan.”
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And when William realised Harry needed support, he told his brother to seek mental health advice.
Finding Freedom, co-authored by Carolyn Durand and Omid Scobie, said: “Each brother wanted real happiness for the other.
“It was precisely because of this that William confronted his brother about his mental health.
“As Harry later recounted in a podcast interview with the columnist and friend Bryony Gordon, who herself has obsessive-compulsive disorder, he said, ‘You really need to deal with this. It is not normal to think that nothing has affected you.'”