Kate Middleton Is 'Deeply Upset' by Prince Harry and Meghan Markle Building Their Brand Amid Royal Health Crises

Prince Harry and Meghan Markle's public life is beginning to bother Kate Middleton, experts claim.

"Not only is there the pressure on William, but also the constant sniping from California. I'm sure he's furious with Harry, he's behaved appallingly," Tom Bower told an outlet.

"While they're establishing this so-called brand Sussex, the family here is going through torment. After Charles' diagnosis, Harry came over for half an hour, and that's it, he's done nothing else," he continued. "I can imagine that Kate and William are deeply upset by having the Sussexes' brand operation rubbed in their face while they're going through this tragedy."

In March, Kate returned to Instagram to update fans on her health.

"I wanted to take this opportunity to say thank you personally for all the wonderful messages of support and understanding whilst I've been recovering from surgery," Kate began in a video. "It has been an incredibly tough couple of months for our entire family. In January, I underwent major abdominal surgery in London. At the time, it was thought that my condition was non-cancerous. The surgery was successful, however, tests after the operation found cancer had been present. My medical team therefore advised I should undergo preventive chemotherapy, and I am now in the early stages of that treatment."

"This of course comes as a huge shock, and William and I have been doing everything we can to process and manage this for our young family. It has taken my time for me to recover from my surgery," she continued. "Most importantly, it has taken us time to explain to George, Charlotte and Louis and to reassure them I am going to be OK. As I've said to them, I am well. Having William by my side is a great source of comfort, and the love and support and kindness that has been shown from so many of you. As a family, we need some time, space and privacy while I complete my treatment. My work has always brought me a deep sense of joy. I must focus on making a full recovery. At this time, I am also thinking of those whose lives have been affected by cancer. Please do not lose faith or hope. You are not alone."

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OK! previously reported an insider claimed the Princess of Wales isn't willing to see the Sussexes as she focuses on her health.

"[It's] the last thing she needs," a source told an outlet. “Meeting with Harry is the last thing that William or Catherine want or need right now. It’s a fantasy.”

“It’s not about apologies or who said what, it is about protecting his family," they continued. “Kate is recovering from cancer, and they are avoiding stressful situations."

Bower spoke to The Sun.