Prince Harry and Prince William have barely spoken to each other in months other than to wish each other happy birthday, a royal author has claimed.
Robert Lacey's book Battle of Brothers focuses on the alleged difficulties in Princes William and Harry's relationship in recent months.
He claims the brothers' fallout is a lot worse than many people believe, and warns that if it can't be healed it will be one of the "traumas" that historians look back on and say changed the royal family forever.
He writes that the whole modern royalty was built on the assumption that William and Harry would stick together, but Meghan joining the royal family has changed this, he claims.
And the relationship has deteriorated so much lately, William and Harry have only spoken in the last few months to wish each other Happy Birthday, he claims in The Sun.
This is despite their father Prince Charles falling ill with coronavirus and recovering from the disease.
An extract from Mr Lacey's book reads: "What you’ve got to realise is that the whole strategy of the monarchy was based on them sticking together. Meghan changed all that. She is difficult. She has an incredible and dangerous level of self-belief.
"But the Palace got this very wrong, as it always does with the second-born. They always treat the second-born badly, not to say cruelly. It happened with Princess Margaret. It happened with Prince Andrew. It’s the classic heir and the spare thing. They just don’t know what to do with the spare. And they certainly didn’t know what to do with the spare’s wife."
Mr Lacey also warned in his biography that if William and Harry don't patch up their feud it will be a 'trauma' similar to mum Diana's death that will change the monarchy forever.
Mr Lacey claims the system of monarchy has conspired to fan the flames of resentment between William and Harry, rather than attempt to find a compromise.
"Some say, 'Oh, it doesn’t matter. It will blow over,'" the author told the Daily Mail.
"But that’s not what historians will be saying in ten years’ time.
"If this breach between the brothers is not healed in some way it will come to stand with the Abdication crisis and the death of Diana as one of the traumas that changed the monarchy.
"There is time to change things in a positive direction, but at the moment the Palace is not working in that direction."
Harry turned 36 last month, which reportedly saw members of the Royal Family reunite on a Zoom call to wish him happy birthday.
Although Archie, Harry and Meghan's son, was on the zoom call, William was allegedly absent, sparking fears they are still feuding.
A source said: “William sent his birthday best wishes. There was some excuse made about why he wasn’t there.
“It was a bit awkward that William and Kate weren’t there.”
Meanwhile, William and Harry issued a rare joint statement earlier this year slamming speculating about their relationship.
Harry also previously spoke about his relationship with William and said: “Inevitably stuff happens. But we’re brothers, we’ll always be brothers.
“We’re certainly on different paths at the moment. I’ll always be there for him and as I know, he’ll always be there for me. We don’t see each other as much as we used to because we’re so busy but I love him dearly.”
The Mirror Online has contacted the Palace for a comment.
