The murder trial is finally underway for Lori Vallow Daybell, 49, the mother of three whose religious beliefs about zombies and the end of the world are cited as partial motives for the alleged murders of two of her children and her husband's previous wife.

Opening arguments in the trial in Boise, Idaho, began on Monday. If convicted, Vallow Daybell could face life in prison. She and her husband, Chad Daybell, 54, were indicted nearly two years ago. They're now being tried separately.

Here's a brief recap of Vallow Daybell's history, and the case against her:

What is Vallow Daybell accused of?

Vallow Daybell and Chad Daybell were indicted in May 2021 on nine criminal charges, including murder and/or conspiracy charges in three deaths.

Vallow Daybell is accused of killing her two youngest children, Tylee Ryan and Joshua Jaxon "JJ" Vallow. Tylee was nearly 17 when she and JJ, 7, were last seen alive in September 2019. The children's bodies were found in June 2020, buried on property in Rexburg, Idaho, owned by Chad Daybell.

Even before the remains were found, Vallow Daybell was charged with felony desertion of a child, as well as obstruction.

She is also accused of conspiring to murder Tammy Daybell, Chad's then-wife who was found dead in her home in October of 2019 — less than one month before he and Vallow got married in Hawaii. He is Vallow's fifth husband.

In a separate case in Arizona, Vallow was also indicted on conspiracy murder charges for allegedly arranging for her brother, Alex Cox, to shoot and kill her fourth husband, Charles Vallow, in July of 2019. Alex Cox died in December of 2019, of what was determined to be natural causes.

How do her beliefs factor into the case?

Prosecutors say Vallow Daybell and Daybell were focused on the "end times" and doomsday scenarios, and that they shared beliefs about people manifesting dark energy.

The indictment cites text messages between the pair "regarding death percentages for Tammy" Daybell, as well as messages about her being in limbo, and Tammy "being possessed by a spirit named Viola."

On Monday, Fremont County Prosecutor Lindsey Blake told jurors that Chad Daybell and Lori Vallow Daybell portrayed themselves as religious figures called "James and Elaina."

Blake said Vallow Daybell purported to be able to "rate" people, detecting whether they might be under the thrall of an evil spirit's dark energy.

"The defendant used 'casting' that involved prayer and energy work," Blake told the jury on Monday, according to East Idaho News. "Often this casting didn't work and the beliefs evolved to zombies. A common theme was the body had to be destroyed."

The zombie story emerged in 2020

In 2020, Rexburg police detective Ron Ball said in an affidavit that Vallow Daybell's close friend Melanie Gibb described hearing her say that Tylee had become a zombie — a concept Vallow Daybell had picked up from Daybell.

Gibb heard Vallow Daybell call Tylee a zombie — after Tylee had refused to babysit JJ — to which Tylee replied, "Not me, mom," according to the affidavit. Gibb said Vallow Daybell later concluded that JJ had also become a zombie.

Daybell and Vallow Daybell told Gibb that they were part of the "Church of the Firstborn" and had a special mission, directed by the Book of Revelation, Gibb told the detective.

"They also stated their mission was to rid the world of 'zombies,' " Ball wrote.

In their eyes, zombies are controlled by dark spirits — and the host body can only be released through physical death, Ball added.

"Gibb was present with Lori Vallow when Chad Daybell first instructed Lori about his theories of zombies over the phone in early 2019 in reference to Charles Vallow," Ball wrote.

Months later, Charles Vallow was killed.

Money is also a big part of the case

Prosecutors accuse Vallow Daybell and Daybell of benefiting from the three deaths by funneling money toward themselves, in the form of federal benefits and an insurance payout. Their goal, Blake said, was to create a new life together.

Charges against Vallow Daybell include grand theft, with the U.S. government as the victim, after she received Social Security funds intended for the care of Tylee Ryan and JJ Vallow and did not report Tylee's death.

"The defendant used money, power and sex to get what she wanted," Blake said in court, according to The Associated Press. "It didn't matter what it was."

Prosecutors say that in the month before his wife died unexpectedly, Chad Daybell signed paperwork to boost her life insurance to the maximum allowed under the policy.

The case has inspired a TV series and a book

Vallow Daybell's son Colby Ryan and other relatives told their side of the story about her and Chad Daybell last fall, when Sins of Our Mother, a true-crime series, premiered on Netflix in September. The series is directed by Skye Borgman.

There's also a book about the case: When the Moon Turns to Blood, by Portland, Oregon-based journalist Leah Sottile, who says Lori Vallow went from being a "suburban mom in yoga pants" to someone caught up in an extreme subculture.

"I have found in my own reporting that Lori Vallow and Chad Daybell really existed at the fringes, the far right fringes of the Church of Jesus Christ of Latter-day Saints," Sottile told member station Boise State Public Radio, "and that they ... kind of were able to meet because of this ecosystem of extremism that exists there."

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