Police Cite Natural Causes in Death of Lori Vallow's Third Husband She Allegedly Wanted to 'Kill'

John Roark/AP/Shutterstock Lori Vallow, at left, and Joseph Ryan

Police say Lori Vallow's third husband Joseph Ryan died of natural causes, concluding a review into his 2018 death begun after they obtained a recording in which the Idaho mom who is under investigation in the deaths of her two kids could be heard saying she "was going to kill him."

Authorities had previously said Ryan died of a heart attack. They found nothing in the review launched last fall to reverse that conclusion, a spokesman for Phoenix police, Mercedes Fortune, tells PEOPLE.

Vallow and her fifth (and current) husband, Chad Daybell, otherwise face multiple criminal charges tied to Vallow's two children, 7-year-old Joshua "J.J." Vallow and 17-year-old Tylee Ryan, whose bodies were found in June, buried on Daybell's Idaho property more than six months after the kids had been reported missing.

Neither Vallow nor Daybell, an author who wrote about doomsday scenarios, have been charged with the children's deaths. But Madison County, Idaho, prosecutor Rob Wood said he is leaning toward doing so during a conversation with Vallow's sister, Summer Shiflet. A recording of that conversation made by Shiflet's attorney was obtained earlier this month by East Idaho News.

RELATED: Prosecutors Plan to Charge Lori Vallow & Chad Daybell with Conspiracy to Murder Kids: Recording

For now, Vallow is facing charges of desertion and nonsupport of dependent children, resisting or obstructing officers, criminal solicitation to commit a crime, contempt of court and willful disobedience of court process or order.

Daybell is charged with two felony counts of conspiracy to commit destruction, alteration or concealment of evidence and two felony counts of destruction, alteration or concealment of evidence.

Both have pleaded not guilty to the allegations.

Rexburg Police Department (2) Joshua “J.J.” Vallow, at left, and Tylee Ryan

Police in Arizona, where Vallow lived before moving to Idaho to be with Daybell following the death of her fourth husband, Charles Vallow, reopened an investigation into Joseph Ryan's death after they obtained a recording in which she reportedly talked about wanting to kill Ryan and cited the Bible as justification, Fox13 and AZ Family report.

Ryan was found dead in his Phoenix apartment in April 2018. His body wasn't discovered for more than a week, after which authorities notified Vallow, who was listed as his next of kin despite the fact that their marriage had ended 14 years earlier.

His cause of death eventually was ruled as a heart attack, and his body was cremated.

But the recording, made six months after he died, raised questions.

RELATED: Police Reviewing Death of Lori Vallow's Previous Husband After Concerning Audio Recordings of Her

"He told everybody that I was this lying, crazy Mormon and got up in court and said all these horrible things about me and turned it around to where the judges believed him instead of me," Vallow is heard telling a group of people in the recording, which was obtained by East Idaho News. "I went through a lot of years of this kind of hard stuff, and I was going to murder him. I was going to kill him, like the scripture says. Like Nephi killed — just to stop the pain and to stop him coming after me and to stop him coming after my children."

The 40-minute recording, which was sent to Ryan's sister who then shared it with police, is from an October 2018 gathering of people for the Second Coming of Christ.

"I just felt I couldn't take it anymore, and I would go through the scriptures and I would find all the things like, if he comes against you once, if he comes against you twice, three times then you can kill him. It says it in the scriptures!," Vallow said in the recording. "I was like, there it is, there's my answer. I don't want to do anything wrong. I do not have a murderous heart. I just want it to stop the bleeding and stop the pain."

Vallow's lawyer did not previously respond to PEOPLE's request for comment on the recording and the renewed investigation.

Rexburg Police Department ; Madison County Sheriff's Office/AP/Shutterstock Chad Daybell, left, and Lori Vallow

Vallow and Daybell bonded over Daybell's writings on religious doomsday scenarios and were married last November. They became the objects of police inquiry that same month, after J.J.'s out-of-state grandparents reported J.J. missing. Police subsequently said the couple appeared to have fled the area; they were located two months later in Hawaii, without the children.

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The boy, J.J., had been adopted by Vallow and her fourth husband, Charles. Tylee was the daughter of Vallow and Joseph Ryan, who were married from 2001 to 2004.

Charles Vallow was shot and killed by Daybell's brother, Alex Cox, in July 2019; at the time Cox said the shooting was self-defense and he was not charged, but police have reopened that investigation. They also are still reviewing the death of Daybell's wife, Tammy, two weeks before he and Vallow wed.

Vallow and Daybell both are currently jailed in Idaho, and remain under investigation for potential murder, attempted murder and conspiracy charges in the Idaho county where Daybell and Tammy were living at the time Tammy died. Confirmation of that investigation was made public in an April 9 letter from the Idaho attorney general's office to the Fremont County Prosecutor's Office, in which the AG's office agreed to assist the local prosecutors in their investigation of those possible crimes.

To date no charges against either Vallow or Daybell have been filed in connection with that investigation.