James Middleton Thanks Sisters Kate and Pippa for Attending His Therapy Sessions

James Middleton attends the launch of the George Charitable Dogs Committee; The Duchess of Cambridge and Pippa Middleton (left) in the Royal Box during day thirteen of the 2012 Wimbledon Championships
James Middleton attends the launch of the George Charitable Dogs Committee; The Duchess of Cambridge and Pippa Middleton (left) in the Royal Box during day thirteen of the 2012 Wimbledon Championships
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David M. Benett/Dave Benett/Getty Images; Adam Davy/PA Images via Getty Images

James Middleton is thanking his older sisters Kate Middleton and Pippa Middleton for supporting him during the darkest days of his depression.

The entrepreneur, 35, opened up in a heartfelt essay for The Sunday Times following the death of his dog Ella, who died earlier this month at age 15 of kidney failure. James has been open about his struggles with depression and has previously credited the cocker spaniel with saving his life.

"Everybody knew how much she meant to me and there was a day they feared the most: the day Ella was no longer in my life. She meant something to all of them too," James wrote in a tribute, published over the weekend.

"My sisters came to some of my therapy sessions. They've always been there during difficult times and they were at my side during the hardest of times as well," he added of Kate and Pippa.

James Middleton
James Middleton

James Middleton/Instagram

RELATED: James Middleton Announces Death of His Dog Ella After 'Short Illness': 'Going to Miss Her Terribly'

James also revealed that "all the family" attended Ella's emotional burial, sharing that Pippa and her husband James Matthews — like Princess Kate and Prince William — have a dog descended from Ella.

"All the family came to say their goodbyes. I can't speak for them but I believe she influenced their lives too," he wrote. "Lupo, Catherine and William's dog, was one of Ella's puppies. My sister Pippa and her husband have a pup from Ella, as do other family members."

James Middleton poses for a photograph with his dogs Inka, Luna, Ella and Mabel at a launch event for this year's Crufts and Friends for Life in Green Park, London.
James Middleton poses for a photograph with his dogs Inka, Luna, Ella and Mabel at a launch event for this year's Crufts and Friends for Life in Green Park, London.

Kirsty O'Connor/PA Images via Getty James Middleton

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Elsewhere in the essay, James reflected on how much Ella meant to him.

"She was next to me through my darkest times, her head in my lap. Winston Churchill would complain that he was followed by the 'black dog' of depression. I had my own black dog but she was my saving grace," he wrote.

A cause close to heart, mental health has long been a key priority of Princess Kate's royal work. Together with her husband Prince William and brother-in-law Prince Harry, she launched the Heads Together initiative in 2016 to smash stigmas surrounding conversations and help for mental health.

The Prince And Princess of Wales Visit Merseyside
The Prince And Princess of Wales Visit Merseyside

Jon Super-WPA Pool/Getty Images Prince William and Kate Middleton

Prince William has highlighted the importance of mental health in every area of life, from medical workers to soccer players, also making combating male suicide a crucial part of his royal work. Meanwhile, Princess Kate has focused on mental health initiatives for mothers and children.

Mental wellness was the topic of discussion during a stop of the Prince and Princess of Wales' first joint engagement this year. On Jan. 13, the royal couple visited the Open Door Charity in Birkenhead to learn how the organization uses culture and creativity to inspire and engage people. They met with four teenagers using the charity's Oomoo program, which offers activities such as dance classes, film nights and other activities.

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"Talking therapies don't work for some people, they're not for everybody," Princess Kate said. "It's so important to have a range of therapies."

Following their chat, Kate said of the teens, "That was amazing. They're so inspiring."

If you or someone you know needs mental health help, text "STRENGTH" to the Crisis Text Line at 741-741 to be connected to a certified crisis counselor.