Marilyn Cardillo Bixler celebrated her 90th birthday with her family in Cabo San Lucas in August 2017, enjoying her first vacation outside the United States by toasting to the next decade of her life over strawberry margaritas. 

Two weeks later, Billy Chemirmir allegedly broke into her apartment at a retirement community in Frisco, Texas, then smothered her to death before fleeing with her jewelry. 

It was a pattern that played out in the Dallas-Fort Worth area from 2016 to 2018, with the accused serial killer racking up 22 murder indictments for allegedly preying on vulnerable senior citizens. He has been convicted in two of the cases and was sentenced to life in prison without the possibility of parole. 

The families of Chemirmir's victims are now left wondering how Chemirmir was able to get away with the brutal murders for so long, and uncomfortable with the fact that as it currently stands, one of the most notorious alleged serial killers in American history will spend the rest of his life behind bars instead of getting the death penalty. 

For Bixler's daughter, Cheryl Pangburn, it wasn't immediately clear that her mother was murdered when she found her on the floor of her apartment on Sept. 17, 2017. 

"I thought it was strange where her body was. I thought it was strange that her glasses were across the room with the frames bent and the lens popped out, so much so that I set them on the console of my car and took a picture. The back of her hair, which she had done every Friday, was an absolute mess and that just didn’t make sense to me," Pangburn told Fox News Digital. 

Still, without any glaring signs of trauma, responding officers noted that she was on hypertension medication and a medical examiner marked her death as due to natural causes. 

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Several months later in March 2018, Pangburn's world began to unravel when she received a Facebook message from someone she went to high school with years ago. 

"She sent me a message that said, 'My mom was also a victim of Billy Chemirmir. My condolences. If you would ever feel comfortable talking, here's my number,'" Pangburn said. 

"As I'm sitting in this appointment, I have no idea what she's talking about. I google search the name Billy Chemirmir, and it just pulls up this serial killer's story," she said. "I'm horrified, but things are starting to make sense." 

Marilyn Bixler with her daughter

Marilyn Bixler, one of Billy Chemirmir's alleged victims, with her daughter, Cheryl Pangburn.  (Cheryl Pangburn)

When Pangburn received that message, Chemirmir's spree of murders had just come to an end after he failed to kill 91-year-old Mary Bartel. 

Bartel, who lived at a retirement community in Plano, Texas, detailed in a deposition played at trial how a suspect forced his way into her apartment on the evening of March 19, 2018, and smothered her with a pillow until she lost consciousness. When she came to, she was taken to a hospital but later found that her gold wedding band, a diamond ring, a gold locket with a picture of her late husband inside, two gold crucifixes, and a silver bracelet had been stolen from her apartment. 

Detectives developed Chemimir as a suspect in the attempted murder of Bartel and started staking out his apartment the next day. Around 6:00 p.m., Chemirmir parked his car at his residence then threw some items in a dumpster. After the detectives arrested Chemirmir on an outstanding warrant, they looked inside the dumpster and found a jewelry box that belonged to 81-year-old Lu Thi Harris. 

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Dallas police officers performed a welfare check on Harris' home and found her deceased inside with lipstick smeared on her mouth and a pillow beside her that was also smeared with lipstick, indicating she may have been suffocated. 

Chemirmir was indicted for Harris' capital murder the next day. 

Texas serial killer in court

Accused serial killer Billy Chemirmir looks back during his retrial on April 25, 2022, at Frank Crowley Courts Building in Dallas.  (Shafkat Anowar/The Dallas Morning News via AP)

As detectives started taking a second look at some unexplained deaths in the Dallas-Fort Worth area, Chemirmir would eventually be indicted on 22 counts of murder, 13 of them in Dallas County and nine in neighboring Collin County. 

In April 2022, Chemirmir was convicted of murder in Harris' death, then was convicted in a separate case for the murder of 87-year-old Mary Brooks this month. 

Chermirmir, who immigrated to the United States from Kenya in 2003, has maintained his innocence and his attorneys told Fox News Digital that he is appealing both convictions. 

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Not all of his victims will get clear closure from the judicial system. The remaining 11 indictments in Dallas County were dismissed by the district attorney's office last week after securing the two convictions and resulting life sentences. 

Ellen French House's mother, Norma Wilson French, was among those 11 dismissed indictments. 

"Not only was it another horrible feeling but the paperwork doesn’t even have her name on it," House told Fox News Digital. "Just a number now I guess." 

Billy Chemirmir

Defendant Billy Chemirmir listens to motions and language being discussed and sent to the jury in his capital murder trial at the Frank Crowley Courts Building in Dallas, Nov. 19, 2021.  (Tom Fox/The Dallas Morning News via AP, Pool)

French was among Chemirmir's first alleged victims in October 2016. House had the opportunity to face Chemirmir in court during victim impact statements earlier this month. 

"This is my beautiful mother. This is my mother after you pried her wedding ring off of her finger that she couldn’t even get off," House told Chemirmir in court as she held up two images of her mother, one of French alive and another after she was killed. "You have robbed me not only of my beautiful, cherished mother, but you've also stolen the Ellen that I was."

House said after the sentencing that she hopes the Collin County district attorney seeks the death penalty after seeing Chemirmir's unflinching behavior in the courtroom. 

"I can tell he's just not there. He just reeks evil," House said. "I made really good eye contact with him several times but no expression whatsoever."

Norma Wilson French

Ellen French House and her mother, Norma Wilson French, one of Billy Chemirmir's first alleged victims in October 2016.  (Ellen French House)

Dallas County District Attorney John Creuzot, a Democrat, initially sought the death penalty, but later decided to pursue a life sentence in the two cases for which Chemirmir was convicted. 

"We have accomplished what we set out to do. There is no question that Billy Chemirmir will spend the rest of his life behind bars," a spokesperson for Creuzot's office told Fox News Digital. 

"The pain and loss he has caused will never be erased, but we can all sleep better at night knowing he has, in effect, indeed received a death sentence. Billy Chemirmir will die in the state penitentiary."

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While the 11 other cases in Dallas County were dismissed, there are still nine pending indictments in Collin County. Pangburn, Bixler's daughter, said there was a "sense of shock" when the families were first told that prosecutors would not seek the death penalty in Dallas County, but they are still hopeful. 

"She was a joy and she was absolutely thriving where she was, she absolutely loved living where she lived, and it just ended tragically," Pangburn said. "It's the ultimate crime, it deserves the ultimate punishment." 

A spokesperson for the Collin County District Attorney's Office declined to comment, citing a policy against discussing ongoing cases. 

Miriam Nelson

Miriam Nelson (right) with her daughter, Karen, and her grandson, Jason.  (Karen Harris)

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The families of several of the victims have now formed a nonprofit called Securing our Seniors' Safety, helping usher two new laws through the Texas legislature, one ensuring that medical examiners notify families when a relative's death certificate is amended and another enhancing regulations on cash-for-gold shops. 

"What I'd like to do is raise awareness for all the senior living facilities – have more meetings about security, if you're going to put the onus of security on your residents, then make them more aware of how to be safe," Karen Harris, whose mother, 81-year-old Miriam Nelson, was murdered on March 9, 2018, at a senior living facility in Plano. 

"This was a vulnerable, trusting generation of ladies that were primarily widows. They thought they were living in really safe, nice places, and they were nice places, but they weren't safe."