Kate Middleton is leaning on Prince William amid her cancer diagnosis. 

A source tells ET that, despite all the erroneous speculation in the press, William “has been at Kate’s side,” and that “his primary goal in all of this has been to support his wife and his children.”

The Princess of Wales, 42, thanked her husband during her announcement on Friday that she has been diagnosed with cancer. 

“Having William by my side is a great source of comfort and reassurance too, as is the love, support and kindness that has been shown by so many of you,” Kate said in a video statement. “It means so much to us both. We hope that you’ll understand that as a family we now need some time, space and privacy while I complete my treatment. My work has always brought me a deep sense of joy and I look forward to being back when I’m able, but for now I must focus on making a full recovery.”

The same source tells ET that Kate filmed the video on March 20 and she started receiving cancer treatment shortly after her abdominal surgery in January.

William and Kate struggled to tell their children, the source explains, because they wanted to shield them as much as possible.

“Children process information in different ways. Their primary concern was to be able to explain this to the children in a way that was reassuring, and they could process,” the source said.

Kate shares three children with William — Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5.

On Friday, Kate revealed that, following her abdominal surgery, it had been thought the procedure turned out to be non-cancerous but tests conducted after her surgery showed doctors “found cancer had been present.”

She added, “My medical team therefore advised that I should undergo a course of preventative chemotherapy and I’m now in the early stages of that treatment.”

“This of course came as a huge shock. And William and I have been doing everything we can to process and manage this privately for the sake of our young family,” Kate said in her video statement. “As you can imagine, this has taken time. It has taken me time to recover from major surgery in order to start my treatment. But, most importantly, it has taken us time to explain everything to George, Charlotte and Louie in a way that’s appropriate for them and to reassure them that I’m going to be OK. As I said to them, I am well, and getting stronger every day by focusing on the things that will help me heal.”

Following Kate’s photo scandal, Kate and William were spotted together on March 11 riding in the backseat of a car and on their way to a private appointment. Then on March 18, Kate was spotted with William again, this time at a farm shop not far from their Windsor home.

“Kate was out shopping with William and she looked happy and she looked well,” an eyewitness told The Sun.

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