By Andrea Lucia

FRISCO, Texas (CBSDFW.COM) – To celebrate Marilyn Bixler’s 90th birthday, her family flew her to Cabo San Lucas.

“She took a shot of tequila and said, ‘91, here I come’,” recalls her daughter, Cheryl Pangburn, who remembers thinking how incredibly healthy she seemed.

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Marilyn Bixler (credit: Cheryl Pangburn)

Weeks later, Pangburn dropped by her mother’s apartment in Frisco’s Parkview Retirement Community and discovered her dead.

“It didn’t make sense to me…” she said. “Her body was perfectly positioned between the couch and the coffee table.”

The back of Bixler’s recently styled hair was a mess. The eyeglasses she always wore were bent and missing a lens.

But, there was no investigation into her death by police or anyone else.

“It was very much the sense that it’s expected. They’re in a senior facility. 90 years old. It was just a routine thing, it seemed like, at the time,” said Pangburn.

Cheryl Pangburn (CBS 11)

Six months later, local police began linking the deaths of elderly women to a suspected serial killer named Billy Chemirmir.

Investigators reviewed hundreds of deaths and in August of 2018, nearly a year after Marilyn died, the Collin County Medical Examiner changed the cause of death on her death certificate to “undetermined.”

Another half year would go by before her family found out.

“I mean, that’s how I was notified…” said Pangburn, pointing to a page in a binder displaying the Facebook message she received from an acquaintance in March of 2019.

“Cheryl, you may not remember me,” it begins.

The writer explained her own mother had been murdered by Chemirmir and she’d recognized Marilyn’s name on a police list of suspected victims.

“I thought since you went through the same thing I did you might find some some comfort in talking,” she wrote.

Pangburn was confused.

“I had no idea what she was talking about… or who she was even referencing…” she said.

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She searched online and found the news of deaths similar to her mother’s that were being reclassified as murder.

“I literally felt sick,” she said. “The police department identified that she was a potential victim and didn’t reach out to us. The medical examiner changed the cause of death and didn’t reach out to us.

She believes she missed an opportunity to ask questions and to provide evidence.

Like other victims, her mother was missing jewelry, though she never reported that to police.

“The feeling was so horrible…” she said.

Pangburn’s experience is now the inspiration for Texas House bill 723, legislation requiring written notice to next of kin of changes to a death certificate.

“I just can’t imagine finding that out on social media instead of having a professional person explain this to you,” said State Representative Jared Patterson who filed the bill.

Collin County Medical Examiner, Dr. William Rohr, told CBS 11, he had assumed Frisco Police had notified the family.

A police spokesperson said, an investigator had spoken with Dr. Rohr’s office at one point in the investigation and was aware the death certificates of several possible victims would be amended, but not when.

“Unfortunately, we were not aware that it had been completed until after Mrs. Bixler’s family contacted us,” read a Frisco Police statement.

After CBS 11 showed him the legislation, Dr. William Rohr responded, “The house bill is a good law even for routine changes of death certificates, and easy to comply with. No need to wait until September.”

Tuesday, Rohr confirmed his office started sending out letters by mail to confirm any changes to cause of manner of death on a death certificate.

Pangburn still plans to pursue the legislation to ensure the same is happening statewide.

She’ll fight if necessary for this and other bills proposed by the families of Chemirmir’s alleged victims.

“Whatever we have to do. And whatever we can do. We’re going to do it, to make sure that things change and that this doesn’t happen again,” she said.

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Cheryl Pangburn and her mother, Marilyn Bixler (credit: Cheryl Pangburn)

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