The brother of the Princess of Wales has shared insights into what Kate is truly like in private, explaining how she has supported him during his most challenging times.

In a seldom-given interview, James Middleton, 38, expressed admiration for the special bond he shares with his sister Kate, 43, noting that their relationship has not altered since her entry into the Royal Family.

He said he has always just seen Kate as his big sister – and that she has always been there for him. 

James also explained that behind the royal image she must maintain, the Princess of Wales is a sensitive, strong and emotionally intelligent woman. 

He told The Mirror: ‘I’m incredibly fortunate to have my two sisters, not just as siblings, but as friends.

‘They’ve seen me at my best and at my lowest, and they’ve always been there when I’ve needed them.

“The love between siblings is unique; while you can’t choose your siblings, and it might require effort and can be complex, when it is strong, it is among the most powerful connections that exist.”

James also opened up about the mental health crisis that he experienced back in 2017. 

He said that Kate, along with their sister Pippa 41, and mother Carole, 70, helped him make it through to the other side. 

James has also previously credited the Prince and Princess of Wales for the work they have done on reducing stigmas surrounding mental illness.

The family grew up in Berkshire – with the Princess of Wales marrying Prince William in 2011 after they met at St Andrews University. 

James previously spoke about his sister’s shock cancer diagnosis, saying it had been a ‘challenging time’ for the entire family.

He told The Times: ‘For her and her family, it was a challenging time, and I know for us and our bigger family it was a challenging time.’

The entrepreneur, who now operates dog food business James & Ella, explained how the process taught him to offer unconditional support wherever possible.

‘Being there for someone is such an important part, and it doesn’t necessarily have to be on your terms, and it shouldn’t be on your terms,’ he said.

‘It should be on their terms; unconditional: “I’m not doing it for something in return. I’m doing it because I love you”,’ he continued.

In early September last year, the Princess of Wales revealed that she had completed chemotherapy and was ‘taking each day as it comes’ in her recovery journey.

Father-of-one James, whose book Meet Ella: The Dog Who Saved My Life has just been published in the UK in paperback, also opened up about the time he came close to suicide, standing on the ledge of his parents’ Chelsea house ready to jump.

His childhood dog, Ella, was looking up at him from below as if imploring him to come down, which he thankfully did.

James detailed how he was diagnosed with Attention Deficit Disorder and clinical depression in 2017, having struggled in school and university all his life owing to his dyslexia.

He began a course of Cognitive Behavioural Therapy, and even found a consultant psychiatrist who was open to allowing his dog Ella to sit in on their sessions.

Earlier this month, Kate released a video revealing how the ‘healing power of nature’ played a vital role during her treatment for cancer.

The series, which will be released on Kensington Palace’s social media channels, began with ‘Spring’, a three-minute film narrated by Kate, which features footage of her and Prince William on the Isle of Mull earlier this month.

The other three short films will be released across the course of the year, with the Summer, Autumn and Winter editions to be released in due course.

Referring to how she sought comfort and strength from being outdoors with her family during her cancer battle last year, Kate said: ‘Over the past year, nature has been my sanctuary.

‘The natural world’s capacity to inspire us, to nurture us and help us heal and grow is boundless and has been understood for generations.

‘It is through nature that we can fully understand the true interconnectedness of all things, the importance of balance and the importance of renewal and resilience.

‘Connecting to nature helps us to experience a deeper sense of ourselves, the world around us, and each other.’

She added: ‘Spring is a season of rebirth, of hope and new beginnings. From the dark days of winter, the outside world quietly awakens with new life, and there comes a sense of optimism, anticipation, and positive, hopeful change.

‘Just as nature revives and renews so too can we. Let us reconnect to nature and celebrate a new dawn within our hearts.

‘It is often from the smallest of seeds that the greatest change can happen, and in this ever-growing complex world, we need to hold on to what connects us all.

‘Spring is here, so let’s make the most of it together.’