Prince William is said to be "devastated" by claims made by his younger brother, Prince Harry, in his forthcoming memoir, Spare, and subsequent TV interviews.
In the book, the Duke of Sussex has shared details of a physical fight between him and William, and claims that the Prince of Wales was sceptical of his relationship with Meghan Markle from the beginning.
Speaking on Good Morning Britain on Monday, The Sunday Times' Royal Editor, Roya Nikkhah said: "[William] is devastated. The quote I used yesterday was 'he's burning inside'. That is how he's feeling. He's chosen not to go toe-to-toe with his brother and not retaliate, it's not what he does."
WATCH: Prince William 'devastated' by Prince Harry's memoir
She added: "He's devastated that so much personal stuff has come out, particularly given my understanding of what he knows about his brother, his experiences with his brother, how he looked after him. But I think that he feels very strongly that it's just not right to come out and go 'No, this didn't happen, that happened in a different way'. That's not how he rolls."
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Prince Harry's interview with Tom Bradby also aired on ITV1 on Sunday evening, in which he claimed that he had never accused the royal family of racism, and that he does not think they are racist.
After his and Meghan's interview with Oprah Winfrey last year, in which they said that a member of the royal family had asked Harry what colour their baby was likely to be, the couple were widely seen to be suggesting that some within the institution were racist.
And during Harry's appearance on CBS' 60 Minutes with Anderson Cooper, he revealed that he is currently not speaking with William and that it had been "a while" since he last spoke to his brother and father, King Charles.
Yet there is cause for hope as British history is littered with rifts between royal brothers far worse than Harry and William's schism. Here are six fraternal fallouts which turned really nasty.