The Princess of Wales's younger brother James has revealed how the Middletons have supported her through her cancer diagnosis.
Father-of-one James, 37, is releasing a new memoir Meet Ella: The Dog Who Saved My Life, which is published on September 26.
Speaking ahead of the launch, James gave a rare insight into his family's relationship with Kate, 42.
In an interview with Hello! Magazine, James, who lives in Berkshire with his wife Alizee and son Inigo and six dogs, revealed that the Middletons are a very 'close' family.
Reflecting on how they have supported Kate through her cancer diagnosis earlier this year, he said: 'We are certainly a close family that goes through things together.
The Princess of Wales's younger brother James has revealed how their family has supported her through her cancer diagnosis. Pictured with his new book, Meet Ella
'That was the experience I had through my challenges, and I certainly feel like it's something that her [Catherine's] family and our family are doing too.'
He added: 'I know how much the dogs, for me, have helped in taking your mind off something. So I'm certain that for them, Orla is doing her job in supporting her family.'
The Waleses family dog Orla was gift from James, and the relative of his beloved dog Ella.
Just how close the family are was shown in Kate's cancer recovery video earlier this month, which showed an intimate portrayal of the royals like never before.
The clip featured Kate's parents, Michael and Carole Middleton, who were seen playing cards with Kate, William, and their three children, George, Charlotte and Louis at their Norfolk Home, Anmer Hall.
Both Kate and William are famously close to the rest of the Middleton family so the appearance of the Middletons in Kate's most intimate video to date came as little surprise.
Sat around a dining room table, they were filmed playing a card game with their three excited grandchildren and William and Kate in what made for a very light-hearted moment.
The game was sweetly competitive as everyone raced to be the first to put their cards in the middle of the table.
James Matthews, Pippa Middleton and James Middleton attend the wedding of Princess Eugenie of York and Jack Brooksbank in 2018
James Middleton pictured with his older sister the Princess of Wales on a family holiday as children
Kate's parents are said to have spent months at her side, with Carol reportedly supporting her daughter through her cancer treatment at her home in Windsor.
In June, Michael and Carole made an appearance at Royal Ascot, where they were spotted chatting to Prince William.
Prior to this, their last public appearance at been at Kate's annual Royal Carols: Together at Christmas at Westminster Abbey in London in December.
James shared a touching message for his sister following the release of her moving video, which marked the end of her chemotherapy treatment.
British entrepreneur James was quick to remark on the footage, writing in the comment section of the Prince and Princess of Wales' Instagram post: 'I couldn't be more proud', alongside a red heart emoji.
Not only have Carole, 69, and Michael, 75, been by Kate's side, but Pippa Middleton, 41, the royal's sister, also supported the Princess during her health struggle.
The siblings were spotted at Wimbledon together this summer, during one of Kate's rare public outings after her triumphant return to the spotlight at Trooping the Colour in June.
After the Princess announced in March that she was undergoing a course of preventative chemotherapy, James shared a touching message of support for his sister.
He took to Instagram to share a childhood photo with Kate on a hiking trip, saying: 'Over the years, we have climbed many mountains together. As a family, we will climb this one with you too.'
Kate's parents, Michael and Carole, appeared in her intimate cancer recovery video earlier this month
Kate and William are known to be very close with the Middletons. Kate and James are pictured at the Concert For Diana in 2007
As well as featuring the Prince and Princess of Wales, and their three children, the clip also showed Kate's parents (pictured: Carole Middleton)
Prince William chats to his mother-in-law Carole Middleton and cousin Zara Phillips as the royals congregated for the second day of Royal Ascot
James Middleton pictured with his late dog Ella, who died aged 15 after a short illness in January 2023
Royal fans were quick to react at the time, pointing out how entrepreneur James will have been supporting Kate in the same way she was by his side through his battles with depression.
James has previously spoken about how Kate, alongside his parents and sister Pippa rallied round to help him overcome clinical depression.
'I was very lucky that they were willing to be involved and understood that it’s a process, there's no quick fix to it,' he said.
'And understanding the way that my mind works, which may differ from theirs or other people's is a really important part, because it was was a process for me as much as it was a process for them, and I think as a family we grew from that.'
He also spoke about how Kate and Pippa both attended therapy sessions alongside him in support.
'My sisters came to some of my therapy session,' he said. 'They've always been there during difficult times and they were at my side during the hardest of times as well. For that, I am forever grateful.'
It comes after James revealed how his father told him his £32,000-a-year education was a 'waste of money' after he was forced to retake his chemistry A-Level four times.
The Princess of Wales' younger brother opened up about the challenges he faced in school in his new memoir Meet Ella: The Dog Who Saved My Life.
Pictured: James Middleton with his parents Michael and Carole ahead of the Royal Wedding in April 2011
James was a boarder at Marlborough College in Wiltshire - where his older sisters Catherine and Pippa excelled in their studies.
In an interview with The Times, James explained how his mother Carole always encouraged him to invite school friends to their home in Bucklebury on weekends - but he was more concerned with being reunited with the family dog Tilly.
James - who has been diagnosed with dyslexia and Attention Deficit Disorder as an adult - recalled: 'I was an outcast.. alienated from my classmates. But dogs never judged me.'
When he was 18 years old, James had to take a gap year to retake his Chemistry A-Level four times - which he says was a 'humiliating record' for Marlborough College.
At this point, James recalls how his father Michael told him that his private education had been a 'waste of money'. However, James insisted: 'Mum and Dad just wanted the best for me'.
The three Middleton children's education was reportedly funded by a £1.3m trust fund set up by the Princess of Wales great-grandmother Olive following the death of her three brothers.
After his final resit, James got into Edinburgh University and picked geography, criminology and environmental studies modules - but failed his first-year exams.
As a teenager, James had been desperate to have a dog of his own and jumped at the opportunity to adopt a black cocker spaniel puppy - who he named Ella - during his time at Edinburgh.
Having dropped out of university, James was told he would receive no more financial support from his parents but could move in with his sisters at the family's flat in Chelsea.
Pictured: James Middleton with his late dog Ella, who he has now written a book about and named his dog food company after
Pictured: James Middleton with his wife Alizee Thevenet in November 2021. The couple recently welcomed a son called Inigo
Detailing how Ella supported him during this challenging time, James explained: 'She was my shield. Through her I could enjoy things.'
The Prince and Princess of Wales had already been dating for three years when James moved to London - and James admitted he found the public interest in his sister's life 'shocking'.
Describing how William was a 'fantastic support' for the family, James admitted: 'At that time, I was already in a vulnerable state of mind and it was an added pressure.'
In 2017, James was in the midst of a mental health crisis - and in November, he came close to taking a fatal leap off the roof of his London home.
He writes in his memoir: 'As I pace, I look down through the skylight and see my spaniel Ella’s gentle eyes looking back up at me.
'Like me, she has been wakeful all night. She senses my strange, agitated state of mind [...]
'What would Ella do without me? She depends on me and I on her. The feeling is entirely reciprocal [...] In that instant I know I will not jump. What would happen to Ella if I died? How long would she wait alone in the flat for someone to find her?'
The following month, James took Ella and her two puppies to a cottage in the Lake District - where he enjoyed walking them in the wilderness, sourcing firewood and wild swimming.
Describing how his dogs have got him through some of his greatest hours of need, James added: 'I think we can learn from dogs. They’re not thinking about yesterday or tomorrow.
'They’re not even thinking about the next couple of hours. They’re thinking about right now. I’m here, they’re here, in the moment.'
What's more, James shared his love of dogs with the late Queen - who reportedly owned more than 30 corgis in her lifetime.
During his first visit to Sandringham, James recalled how the Queen came up to him and said: 'Did you get my message? Ella is welcome to stay in your room.'
In March 2021, James detailed in an interview with The Telegraph how Ella - who had disapproved of previous girlfriends - 'made a beeline' for his future wife Alizée at a private members club in South Kensington in 2018.
After approaching his future wife to apologise, James said: 'Alizée thought I was the waiter and ordered her drink while continuing to stroke Ella, who at this point was on her back lapping up the attention.'
The entrepreneur - who is the younger brother of the Princess of Wales - shared this photo of him cradling Ella, taken just hours before she died, in January 2023
Mr Middleton told his followers: 'For 15 years Ella has been at my side, from my darkest days to my happiest'
Pictured: James Middleton signing copies of his memoir Meet Ella: The Dog Who Saved My Life
In May 2020, James set up a raw dog food company called Ella & Co named after his beloved dog.
Last January, James announced that Ella had sadly passed away at the age of 15 and said in a touching Instagram post how his beloved dog had supported him 'from my darkest days to my happiest'.
He wrote: 'Ella had a very short illness, she slipped away in my arms at home and is now buried in the garden alongside Tilly. I took this picture just a few hours before she died
'I'm just about holding it together to write this, and despite the fact I knew this day was coming, it doesn’t make it any easier.
'Goodnight my darling Ella, Alizee and the dogs will take good care of me.'
If you have been affected by the issues in this story, you can call Samaritans for free on 116 123, email them at jo@samaritans.org, or visit www.samaritans.org to find your nearest branch.