Friends Mourned Teen's Suspicious Drowning with Her Mother, Then Were Accused of Murdering Her Out of Jealousy

After her 17-year-old daughter was found drowned in a shallow body of water, her waist-length auburn hair hacked off and a 100-lb. log over her body, Irene Avila took comfort in the company of her daughter’s best friend, sharing in their mutual grief.

The friend, Karen Severson, moved into Irene’s home, vowing to find the killer that had left Michele Avila alone in California's Angeles National Forest in October 1985.

"She became like a daughter to me," Irene told PEOPLE in a 1989 interview.

Often, the two stayed up talking about the beautiful, popular girl who everyone called “Missy,” whose body was found by hikers two days after she hopped into a car with another friend, Laura Doyle.

Doyle had later claimed that she had dropped Missy off with three boys driving a blue Camaro. 

For the next three years, the only leads were false ones, and the case went cold. 

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

Chirumbolo told investigators that she had been with the other girls when they headed to the national forest.

As it turned out, Doyle had recently had a break-up with her boyfriend — and she blamed Missy for it. The idea that Missy was to blame, according to PEOPLE's previous reporting, had come from Severson.

Walking in the forest, Doyle and Severson called Missy promiscuous, per the filing, and Doyle grabbed her by the hair and chopped off part of it. The two – who were taller and bigger than Avila, who weighed just 97 lbs. – then forced her into a shallow creek, tied her hands behind her back, gagged her and forced her head under the water until her body stilled. 

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

In July 1988, Doyle and Severson were arrested in connection to Missy’s murder, and were each later convicted of second-degree murder and sentenced to 15 years to life.

After years of mourning the loss of her daughter with her daughter’s own murderer, Irene began to see those first grief-stricken months differently.

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Severson had been obsessed with Missy’s case, visiting her grave several times a week and adorning her bedroom walls with pictures and newspaper clippings about her friend. Often, she took beer to the creek where Missy had been found, drinking at the crime scene.

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

Although Doyle had kept more distance from Irene, she had also occasionally dropped by to visit the grave, per the filing, which adds that she also “furnished false leads” to investigators.

The California Board of Parole Hearings later noted, per the filing, that it was “especially disturbing” that both women had stayed in such close contact with Missy’s family, even as they “carried on a charade” about not knowing what had happened to her.

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 went on to publish a memoir about the murder, leading to the 2015 signing of Missy’s Law, which ensures that convicts in California could not profit off of their crimes.

In a 1989 jailhouse interview with PEOPLE, in which she claimed she was innocent, Severson mentioned a boy she had been interested in, claiming Missy had “moved in on my territory,” and saying, “I just couldn't take it anymore.”

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.”