Deaths of Elderly Women Were Chalked Up to Natural Causes. But Victim's Daughter Suspected Something More Sinister

Shannon Dion was a devoted daughter to her 92-year-old mother, Doris Gleason.

Every Sunday, the duo would attend church together.

But on Sunday, Oct. 30, 2016, their day of worship and prayer turned tragic.

When Dion showed up at Tradition-Prestonwood, a luxury independent living facility for seniors in North Dallas, she found her mother dead inside her apartment.

She was stunned.

“The funeral home arrives, and I tell them that I would like the jewelry off her body,” she says in an upcoming episode of People Magazine Investigates. Titled “A Serial Killer’s Playbook,” the episode premieres Monday, Nov. 25 at 9/8c on ID. (An exclusive clip is shown below.)

“They point to the kitchen countertop where there are these two rings. I said, ‘Where is the necklace?’“

Dion was referencing an Italian, guardian angel necklace that her mother wore all the time, but was nowhere to be found.

“We start looking and the necklace is missing. I don’t know what it was that drove me, but I went to my mother’s purse and got her billfold because there was cash we had just taken out the Friday before, and here it is Sunday morning. There was no cash.”

Dion said she noticed that her mother’s front top dresser drawer was ajar. She also realized that rings and other jewelry were missing.

“That’s when I knew something was wrong,” she says.

Dion said authorities dismissed her claims that something was amiss, saying there was no evidence of foul play.

But in 2018, Dion’s suspicions were confirmed when she got a call from police: It turned out that Gleason was a victim of serial killer Billy Chemirmir, a former health care worker who’d moved to the United States in 2003 from Kenya, who preyed on mostly elderly women living in upscale senior living facilities around Plano and Dallas between 2016 and 2018.

He would often dress as a maintenance worker or health care aid and kill his victims before robbing them. Because the victims were between 76 and 94, their deaths weren’t thoroughly investigated, with most people believing that they had died of natural causes.

His deadly deeds came to light after he attacked 91-year-old Mary Bartel in her ground floor apartment in Preston Place Retirement Community in Plano on the morning of March 19, 2018.

Bartel, who survived the attack, told police about a man knocking at her door, barging in and then forcing her to lie down on her bed. He then grabbed a pillow and attempted to smother her before fleeing with her jewelry.

The attack led police to canvas the complex and learn that the son of a resident reported a stranger loitering in the parking lot a few days earlier.

The man wrote down a license plate for the stranger’s Nissan Altima.

The car belonged to Chemirmir.

Chemirmir was arrested in the parking lot of his Dallas apartment complex the following day after authorities watched him toss into the dumpster a distinct red wooden jewelry box with Asian markings.  

Legal papers found in the jewelry box led them to the home of 81-year-old Lu Thi Harris, who was found smothered to death in her bedroom.

He was convicted of killing two elderly women, including Harris, NBC5 reported.

Chemirmir, 50, was found murdered in his Texas prison cell by his cellmate in September 2023, per the Associated Press.

People Magazine Investigates: A Serial Killer’s Playbook premieres Monday, Nov. 25, at 9/8c on ID.