Prince William has reportedly tried to heal the rift with Prince Harry but was not successful.
William is said to have reached out to his estranged brother after the ITV documentary about the Duke and Duchess of Sussex, where Meghan and Harry opened up about their struggle with royal life.
The Evening Standard reports that William tried to meet his brother at Frogmore Cottage after the show aired in October.
However, that meeting never happened.
In the bombshell ITV documentary, Harry confirmed the much-rumoured feud with his brother, admitting the two were "on different paths".
Following the documentary, a Kensington Palace source said William was genuinely worried about Harry and Meghan's seemingly fragile emotional state.
Following Harry and Meghan's wedding in May 2018, the two brothers did not see each other in private for six months and their relationship was said to be "up and down".
Prince William was Harry's best man. Prince George was a page boy and Princess Charlotte was a flower girl.
At the time of Archie's birth, The Sun also reported that Harry and Meghan had decided to move to Windsor because they "didn't want to live next door to William and Kate".
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In March last year, the Cambridges and Sussexes separated their Instagram accounts after splitting their joint royal household.
Prince Charles was said to be "absolutely furious" about the row between the brothers and the division between the Sussexes and the rest of the royal family.