Friends mourned Missy Avila's death, then were accused of her murder

After her 17-year-old daughter was found drowned in a shallow body of water, her waist-length auburn hair was cut off and a 100-pound weight was added. As Irene Avila placed a log over her body, she consoled herself in the company of her daughter's best friend and shared their common grief.

Friend Karen Severson moved into Irene's house and vowed to find the killer who left Michele Avila alone in California's Angeles National Forest in October 1985.

“She became like a daughter to me,” Irene said in a 1989 interview with PEOPLE.

The two often stayed awake talking about the beautiful, popular girl everyone called “Missy” and whose body was found by hikers two days after she jumped into a car with another friend, Laura Doyle.

Doyle later claimed she dropped Missy off with three boys in a blue Camaro.

For the next three years, the only leads were false, and the case was shut down.

Then another friend, Eva Chirumbolo, came forward, according to the facts of the case, which a judge summarized in response to a writ of habeas corpus previously filed in the case.

Chirumbolo told investigators that she was with the other girls when they made their way to the national forest.

As it turns out, Doyle had recently gone through a breakup with her boyfriend – and she blamed Missy for it. The idea that Missy was to blame came from Severson, according to PEOPLE's previous reporting.

While walking through the woods, Doyle and Severson called Missy promiscuous, according to the filing, and Doyle grabbed her hair and cut off some of it. The two – who were bigger and stronger than Avila, who only weighed 45 kilograms. – then forced her into a shallow stream, tied her hands behind her back, gagged her and forced her head underwater until her body came to rest.

Then they left her, trapped under a log heavier than her own weight.

In July 1988, Doyle and Severson were arrested in connection with Missy's murder and were later each sentenced to 15 years to life in prison for second-degree murder.

After years of grieving the loss of her daughter alongside her daughter's murderer, Irene began to see those first grieving months differently.

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Severson became obsessed with Missy's case, visiting her grave several times a week and decorating her bedroom walls with pictures and newspaper clippings about her friend. She often took beer to the creek where Missy was found and drank at the scene.

She even said Missy was stalking her: she saw her dead friend sitting on the sofa and even blamed her when her van wouldn't start after a trip to the grave site. “Missy, let me go!” she screamed, according to the encounter described in PEOPLE’s previous coverage of the case.

Although Doyle had kept more distance from Irene, she also occasionally stopped by to visit the grave, according to the filing, which said she also gave investigators “false leads.”

The California Board of Parole Hearings later determined, according to the filing, that it was “particularly troubling” that both women remained in such close contact with Missy's family despite “putting on a charade” because they didn't know what was happening to her be .

Both women have since been released. Severson was paroled in December 2011, and after 22 years behind bars, Doyle was paroled in July 2020.

Severson then published a memoir about the murder, which led to the signing of Missy's Law in 2015, which ensures that convicts in California cannot profit from their crimes.

In a 1989 prison interview with PEOPLE in which she claimed she was innocent, Severson mentioned a boy she had been interested in and claimed that Missy had “moved into my territory,” saying, “I just couldn't do it.” endure more.” ”

But Missy's family told PEOPLE at the time that it was more complicated than that. “She was Missy's best friend,” Irene said, “but she was jealous of Missy's family, Missy's looks, Missy's popularity and even Missy's relationship with me.”

Missy's brother Mark added: “Karen wanted to be Missy.”