Ever since Kate Middleton had a romance with Prince William, she developed a good relationship with her then-boyfriend's little brother, Prince Harry. At one point, the Duke of Sussex even caller her "the big sister" he never had. So, the Duchess of Cambridge couldn't help but be broken-hearted and broke down during their emotional farewell as the Sussexes' move to Canada.

A royal insider told Woman's Day New Zealand, via Express, that the future queen consort pulled her brother-in-law to the side and revealed her real emotion about his departure. At the time, the source explained that the mother of three knew that it could be her last opportunity to tell him her feelings. Hence, she couldn't help but be too emotional.

Kate Middleton was trying hard to fight back her tears as she told him that their lack of communication and contact before and after they moved to Canada made the royal family devastated. She also, allegedly, said that they felt utterly "shut out from their lives."

With Prince Harry and Meghan Markle's decision to partly leave the U.K., Prince William's wife felt like she also lost a brother. Katie Nicholl's source added that Kate Middleton had a hard time to accept the estrangement from the royal couple, per Vanity Fair.

It used to be her, Prince William, and Prince Harry as a happy trio. Now, Kate Middleton is saddened by how things turned out. With everything that is happening, it looks like Kate "has taken it all badly." She seemed to be tired and not thrilled as what happened for the past few months had been hard for everyone.

Prince Harry met Kate Middleton in 2003 when she began to have a relationship with Prince William. Since then, they were often seen out and about. They even went on the same royal engagements together when Kate officially joined the royal family in 2011.

They built the Heads Together campaign, attended Trooping the Color, and many more. From the looks of it, Kate Middleton and Prince Harry have a good relationship and are friends, Grazia Daily UK noted.

Kate Middleton is also said to be the one that filled the void that Prince Harry felt when his mother, Princess Diana, died. She became to be the one that he could emotionally lean on. She acted as his big sister.

Prince Harry even often visited the Cambridges at their apartment at Kensington Palace, where Kate Middleton cooked for him, especially his favorite roast chicken. They also shared the same interest, from Game of Thrones box set to cookery lessons. She also gave him love advice. Sadly, this changed when Harry had his own family.