Authorities investigating the death of Tammy Daybell, the former wife of Lori Vallow’s current husband, initially determined that she died from a “cardiac event,” KSAZ-TV reports.

That’s according to court records obtained by the television station, which show Fremont County Coroner Brenda Dye determined Daybell’s death was caused by pulmonary edema or an accumulation of fluid in the lungs that makes breathing difficult, according to the television station.

The 49-year-old woman died on October 19, 2019, at her Idaho home. Although Daybell’s death was initially ruled natural, authorities are scrutinizing it anew and have charged her then-husband, Chad, and Vallow, his current wife in connection with her death.

Prosecutors have charged Chad with killing Daybell, in addition to charges that he and Vallow conspired to kill her. The couple, who married weeks after Daybell died, are also accused of murdering Vallow’s children, 7-year-old JJ and 16-year-old Tylee.

The bodies of Vallow’s children were found on Chad’s property in June 2020 near Rexburg, Idaho, nine months after they went missing.

At the time the bodies were found, Vallow was in custody on charges of obstruction of justice and deserting her children.

Vallow also faces charges of conspiracy to commit murder in Arizona in connection with the death of an earlier husband, Charles. Vallow’s brother, Alex Cox, shot him in July 2019 and died in December 2019, reportedly from a blood clot.

Cox also reportedly tried to shoot Daybell 10 days before she died.

Daybell’s body was exhumed last year and another autopsy was completed in February, but the results have not been released.

KSAZ-TV obtained a copy of the application for probate of will and appointment of a representative, which included Daybell’s death certificate revealing the initial cause of death.

Vallow is scheduled to go on trial in October. She has pleaded not guilty to the charges.

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[Feature Photo: Handout]