Josh Dean, a whistleblower with ties to Boeing supplier Spirit AeroSystems, has passed away due to a sudden illness, the Seattle Times reports.

His death raises concerns within the airline industry, coming less than two months after the gunshot death of John Barnett, another whistleblower who had raised safety issues related to Boeing planes.

Mr. Dean, 45, was a former quality auditor at Spirit AeroSystems, who had come forward as one of the initial voices to highlight potential willful overlooks in the manufacturing process of the beleaguered 737 MAX airplanes.

Known for his commitment to a healthy lifestyle, Dean’s sudden illness took many by surprise. After experiencing difficulty breathing, he was admitted to the hospital and diagnosed with pneumonia followed by an MRSA infection. Despite receiving various treatments, his condition quickly deteriorated, leading to a stroke.

Dean’s legacy includes his advocacy for safety and quality in aviation manufacturing, a cause he shared with fellow whistleblower Barnett. Both men were represented by a legal firm in South Carolina, and Barnett’s death earlier this year — under circumstances still under investigation by police — adds to the gravity of Dean’s passing.

At the time, Barnett’s death was suggested to be self-inflicted, found in his truck in Charleston, where Boeing’s 787 manufacturing facility is located.

Brian Knowles, one of Mr. Dean’s lawyers, told the Seattle Times he wouldn’t speculate on timing and circumstances of the two deaths of Boeing whistleblowers but added “whistleblowers are needed.”

“They bring to light wrongdoing and corruption in the interests of society. It takes a lot of courage to stand up,” he said. “It’s a difficult set of circumstances. Our thoughts now are with John’s family and Josh’s family.”