Rosie Roche, a cousin of Prince William and Prince Harry, has died at 20 years old.

Roche, who was the granddaughter of Princess Diana’s uncle, died at her family’s home in Norton, Wiltshire, on Monday, July 14, with a “firearm nearby,” according to a report from The Sun.

The outlet reported that her mother and sister found her after she began packing for a vacation with friends, and a firearm was found close by inside the property.

A coroner in Wiltshire and Swindon has opened an investigation, which has been adjourned until Oct. 25, according to The Sun.

Coroner Grant Davies said that police “have deemed the death as non-suspicious and there was no third-party involvement,” per The Sun.

Roche was a student at Durham University, and was working on her degree in English Literature.

A spokeswoman told The Sun that the royal family’s cousin “will be sorely missed.”

In an obituary published by the Yorkshire Post on Saturday, July 19, family members remembered her as a “darling” daughter, sister and granddaughter.

“Roche, Rosie Jeanne Burke. Died on Monday 14th July 2025,” the obituary states. “Darling daughter of Hugh and Pippa, incredible sister to Archie and Agatha, Granddaughter to Derek and Rae Long.”

“Private family funeral. A memorial service will be held at a later date,” it added.

The news of the 20-year-old’s death comes more than one year after Thomas Kingston, a British financier who was the husband of Lady Gabriella and former boyfriend of Pippa Middleton, died at age 45.

The Feb. 25, 2024 death of Kingston was described as “impulsive” and “unexpected” at a pre-inquest review, according to the BBC. Kingston died from a catastrophic head injury, and a gun was found near his body at his parents’ home in the Cotswolds, spokesperson for the coroner’s office previously told PEOPLE.

In December, Lady Gabriella, who is a second cousin to King Charles, broke her silence during an inquest at Gloucestershire Coroner’s Court, revealing the circumstances surrounding her husband’s death.

Can’t get enough of PEOPLE’s Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more.

In her emotional witness statement, Lady Gabriella, 43, expressed her belief that her late husband’s “impulsive action” was likely triggered by medication he had been taking in the weeks leading up to his death, according to The Telegraph.

Roche’s family and a spokesman for Prince William declined to comment to The Sun.