The feud between Prince Harry and Prince William remains to be a hot topic until today. As a new book reveals how the Duke of Sussex lashed out at his brother over his romance with Meghan Markle, a royal expert believes he should make amends with Kate Middleton's husband.

A Channel 5 documentary, "2021: The Queen Terrible Year," discussed the relationship between Prince Harry and Prince William. Royal expert Camilla Tominey said everybody knew their bond had changed after Meghan's husband revealed they "were on different paths."

From here, there were claims there had been tensions between them. Knowing Queen Elizabeth II is a "conflict avoider by nature," it may still trouble her to see his two grandsons "not being close," Express noted.

Royal photographer Arthur Edwards added it might upset the monarch to see her family not talking to each other. So, he said Prince Harry was the one who should make the first move to make things right.

It had to come from him and his wife in a "big way." He believed these two could change the situation if they really wanted to do so.

Edwards found it "not nice" that their feud continues and they barely talk to each other. He added this kind of "sidebar soap opera" between the two could "overwhelm and overshadow" more important events in the royal family.

Since July, Prince Harry and Prince William have yet to see each other again after they unveiled the statue of their late mom, Princess Diana, together. They were seen talking in Kensington Palace gardens before and after the unveiling.

Still, rumors about their feud began again when the controversial prince did not attend the party of the statue's donors. Christopher Andersen's new book "Brothers and Wives: Inside the Prince Lives of William, Kate, Harry and Meghan" claimed Prince Harry was very angry when Prince William questioned his fast-moving romance with Meghan.

He even asked the role of his brother in his life, per Page Six. Allegedly, this event happened in September 2017 when Prince Harry revealed he was about to propose to the former "Suits" star, resulting in Prince William asking him why he was rushing things out.

Aside from his older sibling, Prince Harry's uncle, Earl Spencer, was also said to be hesitant about his relationship with Meghan. Prince William even used Earl's opinion on why they should slow things down.

However, this only made matters worse as Prince Harry saw Prince William actively seeking to have others "interfere" in his personal life. He, then, became angry with anyone who would he perceive as against Meghan.