Idaho prosecutors revealed Chad Daybell's first wife's cause of death Monday during Lori Vallow's murder trial, according to local news. 

Lori Vallow and her husband, Chad Daybell, are accused of killing two of Vallow's children, J.J. Vallow and Tylee Ryan, and Tammy Daybell, who died in 2019.

While authorities have yet to disclose the cause of death for J.J. and Tylee, Idaho prosecutor Lindsey Blake said Monday that Tammy Daybell died of asphyxiation, according to FOX 10 reporter Justin Lum.

Blake also argued that Vallow would have done anything to get Tammy Daybell out of the picture and have Chad Daybell "all to herself."

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Chad Daybell and Lori Vallow

Idaho prosecutor Lindsey Blake argued that Vallow would have done anything to get Tammy Daybell out of the picture and have Chad Daybell "all to herself." (John Roark / The Idaho Post-Register via AP)

The couple first met in 2018 at a Preparing a People conference and shared the belief that they had been married in a past life. They also believed people emit light or dark spirits — sometimes so dark that certain people could be considered zombies, Blake said, according to Lum.

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"Defendant will move any obstacle in her way to get what she wants and she wanted Chad Daybell," Blake argued.

J.J. and Tylee went missing in September 2019 — around the time investigators believe they were murdered on Chad Daybell's Idaho property.

In this aerial photo, investigators search for human remains at Chad Daybell's residence in Salem, Idaho, on June 9, 2020. A mother charged with murder in the deaths of her two children is set to stand trial in Idaho.

Investigators search for human remains at Chad Daybell's residence in Salem, Idaho, on June 9, 2020. (John Roark / The Idaho Post-Register)

On Oct. 9, 2019, a masked gunman appeared outside Tammy Daybell's home as she was getting home from work and fired multiple times, Blake said Monday, according to Lum.

"He can’t do anything right," Vallow apparently said in a statement after the shooting, Blake said, suggesting Vallow knew the gunman's identity. Investigators believe Lori Vallow's late brother, Alex Cox, was behind the attempted shooting of Tammy Daybell.

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Ten days later, on Oct. 19, 2019, Tammy died of asphyxiation, though a medical examiner initially listed her cause of death as natural, resulting from cardiac arrest, according to FOX 10.

Chad Daybell and Lori Vallow mugshots

Lori Vallow and her husband, Chad Daybell, are accused of killing two of Vallow's children, J.J. Vallow and Tylee Ryan, and Daybell's ex-wife, Tammy Daybell. (Madison County Jail)

Months prior to Tammy's death, in July 2019, Alex Cox allegedly shot Lori Vallow's ex-husband, Charles Vallow, to death in Arizona, claiming self-defense. Two months later, in September 2019, Tylee and J.J. went missing for months. Cox died later that year of an apparent blood clot in December 2019.

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Blake said Lori Vallow purchased wedding rings while her children were still missing and Chad and Tammy were still married. J.J. and Tylee were gone for months when police say the couple lied about the children's whereabouts and then slipped away to Hawaii, where they got married in November 2019.

Authorities eventually found J.J. and Tylee's bodies buried on Daybell's property in rural Idaho in June 2020.

Joshua Vallow, 7, and Tylee Ryan, 17, are being sought by police in Rexberg, Idaho. Investigators are saying their mother, Lori Daybell, knows what happened to them but refuses to cooperate.

Lori Vallow and Chad Daybell are accused of killing 17-year-old Tylee Ryan and 7-year-old J.J. Vallow in 2019. (Rexberg Police Department)

Robertson noted that Tylee and J.J.'s cause of death has not been released yet, though he thinks they will be brought up in trial. Investigators found Tylee's remains dismembered and burned while J.J.'s body was wrapped in plastic and tied with duct tape.

Vallow and Daybell allegedly collected J.J.'s and Tylee's Social Security benefits between Oct. 1, 2019, and Jan. 22, 2020, after their murder.

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Authorities arrested Vallow in February 2020 and Daybell in June 2020.

The couple was indicted in late May 2021 on multiple counts each of conspiracy to commit first-degree murder and grand theft by deception, and first-degree murder related to the deaths of Tylee, J.J. and Tammy Daybell, officials announced at the time. Arizona officials in June 2021 also indicted Vallow in the July 2019 murder of her ex-husband, Charles Vallow.