WINNIPEG -- The sister of a Winnipeg man who was found dead in a locked washroom at the Health Sciences Centre in 2018 is now suing the hospital, along with the Winnipeg Regional Health Authority, for an 'utter lack of care' that allegedly resulted in her brother's death.

In a statement of claim that was filed in Manitoba's Court of Queen's Bench on July 8, 2020, Sandra Klassen alleges the hospital's delay in proper diagnosis, and failure to provide proper care, supervision and treatment resulted in the death of her brother, Brian Mervin Childs.

On August 20, 2018, Childs was admitted to HSC for mesothelioma, a form of cancer most commonly caused by exposure to asbestos.

CTV News previously reported that Childs, 61, had other serious health issues and had arranged to have an assisted death, though a date was never decided on.

On August 31, Childs went missing from his assigned floor at HSC. According to the statement of claim, he was found dead 12 hours later in a washroom on the main floor of the hospital.

“How can you lose a patient?” Klassen said in an interview with CTV News in October 2018.

READ MORE: Patient who disappeared in Winnipeg hospital found dead in washroom

“He didn’t choose to die locked in a washroom,” she said. “He should not have been allowed to be left dead in the washroom for all those hours.”

The statement of claim said Childs had pneumonia, which allegedly went undiagnosed during his stay at the hospital. The claim said he was only diagnosed following an autopsy.

The claim seeks an unspecified amount of damages, and names the WRHA, HSC, and a number of unknown doctors, nurses and employees at the hospital who were assigned to care for Childs as defendants.

None of the claims have been proven in court.

In a statement to CTV News, a spokesperson for the WRHA said, since the claims are before the courts, they would not make any public comment on it.

"Any response we have to the claim will be made through the judicial process," they said.

As of Tuesday afternoon, no defense had been filed at the Manitoba Court of Queen's Bench.

-with files from CTV's Josh Crabb