Prince William, Prince Harry’s 20-year-old cousin Rosie’s cause of death revealed

Prince William and Prince Harry’s cousin’s cause of death has been revealed.

Rosie Roche died of a “traumatic head injury,” the Wiltshire and Swindon coroner confirmed to Page Six on Tuesday.

No further details were divulged.

The 20-year-old’s body was found at home by her mother and sister on July 14, with a gun nearby.

Roche had been packing for a trip with friends prior to her passing.

The coroner claimed police have deemed Roche’s death “non-suspicious” without any third-party involvement.

Reps did not immediately return Page Six’s request for comment.

Roche’s obituary — which referred to the late Durham University student as a “darling daughter” and “incredible sister” — was published by the Yorkshire Post on Saturday.

She was one of Edmund “Hugh” Burke Roche and Pippa Long’s three children, with the couple also sharing son Archie and daughter Agatha.

Hugh’s father, notably, was Edmund Roche, Princess Diana’s uncle.

Rosie’s college’s principal, Wendy Powers, released a statement about how “extremely saddened” students and staff members are by her death.

“Rosie had settled into the university and college beautifully and had lots of friends,” Powers wrote of the “sorely missed” English literature major.

“She was loved for her creativity, energy, her love of books, poetry and travel among many other talents,” she concluded.

A private family funeral and a memorial service for Rosie will be held at a later date, according to her obituary.