A woman grew teary-eyed when recounting the moment law enforcement contacted her with shocking news about her mother’s two-year-old death.

Shannon Dion sat with Prosecuting Evil with Kelly Siegler, describing the October 28, 2016 death of her 92-year-old mother, Doris Gleason, as seen in a preview of Season 2, Episode 4. Gleason’s death was quickly passed off as the result of natural causes, and for the next year and a half, Dion had no reason to believe otherwise.

But, a phone call from authorities revealed that not only was Gleason’s death then being investigated as a homicide, but possibly the work of one of the state’s most prolific serial killers.

The call that changed Shannon Dion’s life

“On July 16, 2018, there was a phone message from a task force that was investigating a killer who went around to independent living properties,” Dion told Prosecuting Evil. “My mother, Doris Gleason’s, death was being investigated as a homicide. It took my breath away.”

What Dion was about to learn was that investigators suspected Gleason was an alleged victim of suspected serial killer Billy Kipkorir Chemirmir, whose crimes between 2016 and 2018 have been widely reported by Oxygen.

Dion gave a detailed account of what she remembered about her mother’s tragic passing

“On Sunday, October 20, 2016, I drove my mother to pick her up for church. I get to the door; the door is unlocked,” Dion continued. “I walk in and see her on the floor over by the dining room table, and she was gone.”

Her death, like most of those connected to Chemirmir, was thought to be the result of old age.

“I felt shock … sadness … a bit of devastation; I’d never experienced a death like that,” said Dion. “And, then, when I hear that Mama had been murdered, I am floored.”

More about Billy Kipkorir Chemirmir

When the task force called Dion, they were actively investigating Billy Chemirmir, a Kenyan man accused of posing as a healthcare worker to unlawfully access retirement communities and senior citizen facilities in the Dallas area. He was later suspected of killing at least 22 victims, mostly elderly women, after forcing his way into their residences and smothering them with pillows before taking their jewelry and other valuables.

Chemirmir evaded suspicion from authorities because his victims’ deaths weren’t thought to be the result of foul play. However, the statements of one of his victims, 90-year-old Mary Annis Bartel, would help Texas authorities track a killer down and connect him to nearly two dozen deaths.

Learn more about the case by watching Prosecuting Evil with Kelly Siegler, airing Saturdays at 8/7c on Oxygen.