A reconciliation between Prince William and Prince Harry will be considered "the finest tribute" for their mother, Princess Diana, according to royal biographer Robert Lacey.

He told Express, "Now whether that can happen quickly is another question. I think it's more likely to be the beginning of a slow reconciliation. But it's hopeful."

But one royal expert believes that the statue may even cause the Duke of Cambridge and the Duke of Sussex further apart.

Angelina Levin wrote in the Telegraph that the memorial could cause further heartache, with Prince Harry attempting to "take ownership of his mother's legacy" with his recent boldness.

She said, "Certainly that statue - dreamt up in the last true summer of brotherly love - could end up casting a long shadow over Diana's boys unless they find a way to unite, as she would no doubt want more than anything."

Angela also suggested that the decision of Prince William's younger brother to release a speech at The Diana Awards days after the statue unveiling ceremony was "more than just a coincidence."

"Was this video performance a way of taking ownership of their mother's legacy for himself, albeit couched in the language of LA therapy?" the royal author questioned.

"Having given up his place in the Windsors, has Harry decided to mark his Spencer territory?"

While Prince Harry is focusing on the different parts of his mother's legacy, Prince William is putting most of his time establishing a stable family unit with his wife, Kate Middleton's, family.

Angela added that if only Princess Diana was "more realistic" with the Duke of Sussex about Prince William's future as King, Prince Harry might not have ended up "so disillusioned."

Angela's comment comes after another royal writer, Omid Scobie, who claims that Prince Charles is right not to attend the ceremony because his association with his ex-wife "isn't positive."

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The Duke of Cambridge and the Duke of Sussex will be seen publicly together for the first time since April for the statue unveiling in memory of their late mother at the Sunken Garden of Kensington Palace.

It is said to be one of the late royal's most special places on the palace grounds.

On what would've been Princess Diana's 60th birthday, the event is happening in the afternoon, UK time, with a few guests who are relatives and close friends of the Princess of Wales expected to attend.

The statue was created by Ian Rank-Broadley, while Pip Morrison designed the garden to make the event look exquisite.

According to a royal insider, the statue unveiling is a "small event and a very personal moment for the family."

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