James, Pippa and Carole Middleton are a "bedrock" of support for Princess Kate amid her cancer treatment, a royal commentator exclusively told GB News.
The Princess of Wales announced in March that she had begun a course of preventative chemotherapy following planned abomdinal surgery in January.
James Middleton, 37, was Kate's first family member to publicly wish the Princess of Wales well on social media.
He wrote: "Over the years, we have climbed many mountains together.
Kate's family lives in the Berkshire family
Getty
"As a family, we will climb this one with you too."
This caption was accompanied by an old photograph of Kate and her younger brother as children.
Gareth Russell, a royal author, spoke exclusively to GB News to explain how James, Pippa and Carole Middleton will be supporting the Princess of Wales during her cancer treatment.
He said: "Family is such an important bedrock to anyone undergoing a serious illness and particularly ongoing, lengthy treatment for it.
James Middleton posted this childhood image of himself and Kate on InstagramInstagram / James Middleton"I don't think we'll ever know what the Middletons' role will be, beyond that of a loving family.
"We won't know the specifics because they are very private, and discreet, which is which I think is to their credit."
Carole, Pippa and James all live in the Berkshire area near Princess Kate's home Adelaide Cottage.
The princess's parents, Carole and Michael, live in Bucklebury Manor in Berkshire, where the couple have lived since 2012.
Pippa Middleton and James Matthews married in 2017
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Carole Middleton and Michael Middleton both live in BuckleburyPAMeanwhile, Pippa and her husband James Matthews moved to Bucklebury Farm Park in 2022.
Kate's youngest sibling James and his wife, Alizee Thevenet, additionally live in the Berkshire countryside with their young son, Inigo.
The Prince and Princess of Wales moved to Adelaide Cottage in the summer of 2022.
They live in the four-bedroom cottage with their children Prince George, 10, Princess Charlotte, nine, and Prince Louis, six.