Tammy Daybell's Cause of Death Released During Lori Vallow Trial

Opening statements began Monday in the long-awaited murder trial of Lori Vallow, with prosecutors revealing that her husband Chad Daybell's ex-wife, Tammy Daybell, died of asphyxiation. Lori Vallow is currently on trial for the charges of murder, conspiracy to commit murder and grand theft in connection with the deaths of two of her children, Joshua "JJ" Vallow and Tylee Ryan, as well as Tammy, who was found dead in October 2019 of what were believed to be natural causes at the time.

Speaking in the Boise, Idaho courtroom, Fremont County Prosecuting Attorney Lindsey Blake revealed the results of Tammy's autopsy, according to NBC affiliate KSL of Salt Lake City. Blake said that Tammy's cause of death was determined to be asphyxiation and not a heart attack, as previously believed, telling the court during her opening statements, "[Tammy] died at the hands of another. [Lori] will remove any obstacle in her way to get what she wanted and she wanted Chad Daybell."

Tammy, whom Chad was married to for 28 years before her death, died on Oct. 19, 2019. At the time, Chad reported that Tammy had gone to bed with a cough and didn't wake up. Her manner of death was initially ruled as "natural causes," and no autopsy was performed. Her death was later deemed "suspicious," and her body was exhumed for an autopsy in December 2019. The results of that autopsy were not revealed until the Monday statements, but both Vallow and Daybell were charged with Tammy's murder in 2021.

Tammy's passing came just a few months after Vallow's brother, Alex Cox, shot and killed her ex-husband Charles Vallow. A grand jury charged Lori with conspiracy to commit murder in the first degree nearly two years after his death. She will be tried separately in Arizona in that case.

Vallow is also charged in connection to the deaths of her two children, Tylee and JJ, who were reported missing by J.J.'s grandparents in November of 2019 after they had not been seen since September. Their remains were found buried on a property belonging to Daybell in June 2020. During opening statements on Monday, prosecutors showed the jury photos of the shallow grave where their bodies were recovered. Blake told the court, per PEOPLE, "Money, power and sex, that is what this case is about. Lori used money, power and sex or the promise of those things to get what she wanted."

Vallow has pleaded not guilty to charges of murder, conspiracy and grand theft in the deaths of her children. It was decided in a hearing last month that Vallow will not face the death penalty if she is convicted. Daybell, who is also charged with murder in connection to Tylee, J.J. and Tammy's deaths, will be tried separately.