Prince William Offended by Prince Harry and Meghan Markle 'Deliberately' Using Nickname for Kate Middleton

Prince Harry and Meghan Markle's tension with Prince William and Kate Middleton heightened earlier this year, as an insider revealed the Prince of Wales wasn't happy when the Sussexes didn't call his wife by her first full name, Catherine.

“The fact that Harry and Meghan were unable to bring themselves to use her chosen name, even when they were sending her get-well-soon messages after her cancer diagnosis, was noted," a friend told an outlet. "William takes offense at people calling Catherine ‘Kate,’ because she has asked to be known as Catherine. It’s a fairly simple wish to respect. I’m sure Meghan wouldn’t like it if William started publicly calling her ‘Meghan Markle.’"

The Sussexes often refer to the mom-of-three as Kate, a name typically used by the public and not people within her inner circle.

William is continuing to care for the Princess of Wales as she undergoes cancer treatment, but insiders view his brother's previous statement as insensitive to the Waleses' circumstances.

“Of course, it’s an utterly trivial thing, but those of us who know William know that it is one of the things that pushes his buttons," a source noted. "Pushing his buttons while he was going through his wife’s cancer seemed an entirely unnecessary and deliberate irritation."

“No one’s saying it’s responsible for all the trouble, but deliberately calling someone by a name they don’t like is just bloody rude," they added. "If Harry and Meghan were serious about healing their issue, a good first step would be to call her Catherine.”

As the brunette beauty focuses on her health, William continues protecting her peace, as OK! previously reported the future king and queen are avoiding conversations about the Sussexes for the sake of of their well-being.

"Kate’s still very much focusing on her healing, and they decided to create a firm boundary to protect her from all the stress and upset Harry and Meghan create, which understandably has a negative impact on her physical health, as well as her mental health," a source claimed.

"Kate and William have put a self-imposed ban on anything Meghan and Harry-related, as they take time out to enjoy some much-needed respite and family time," the insider continued.

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When Kate and King Charles announced they have cancer, royal watchers wondered if Harry would temporarily rejoin the royal fold. However, experts claimed William won't allow the Duke of Sussex to return to The Firm.

"It is widely known within the family that Prince William has laid down an absolute ban on Harry returning in any way, shape or form into his former royal family fold," Hilary Fordwich told an outlet.

"If anyone will relent, it would be King Charles III, whom, of course, Prince William won’t challenge, who still misses his ‘darling boy’ and would like to see more of Prince Harry," Fordwich claimed. "However, to this day, after the release of Spare and the Netflix serial, as well as with everything else Harry has said, done, and not done, it’s Prince William who adamantly refuses to even speak to his brother."

The Daily Beast spoke to the sources.