The Idaho mom of two missing kids began “spending all her time” with a doomsday cult before her life took several unexpected and shocking turns, relatives said.

Lori Vallow Daybell was married to her former husband, Charles Vallow, and raising her now-missing children Tylee Ryan, 17, and Joshua Vallow, 7, when she joined the group Preparing a People, according to her sister-in-law.

“Lori was a wonderful, loving, attentive mother,” Kay Vallow Woodcock wrote on Facebook. “Things started changing over the past 18+ months when Lori began spending all her time with a new religious group, that we refer to as a ‘cult.'”

The group is known for its mission to help prepare the people of this Earth for the Second Coming of Jesus Christ.

Woodcock said that at some point earlier this year, Daybell “deserted” her husband for more than two months.

“Charles did his best to save the marriage, of which she had no interest,” Woodcock wrote.

While separated, Charles went to Daybell’s home in Arizona on July 11 to pick up Joshua and take him to school, Woodcock said.

But Daybell’s brother, Alex Cox, shot and killed Charles, claiming self-defense in the deadly incident, Fox News reported. He was never charged and died under mysterious circumstances earlier this month.

Daybell went on to wed Latter-day Saint author Chad Daybell, who has penned several books about the end of the world.

The couple has been cooperating as authorities investigate the disappearance of Daybell’s two children, who were last seen in September.

“We know that the children are not with Lori and Chad Daybell, and we also have information indicating that Lori knows either the location of the children or what has happened to them,” the Rexburg Police Department said. “Despite having this knowledge, she has refused to work with law enforcement to help us resolve this matter.”

Meanwhile, police are also investigating the death of Chad’s first wife, Tammy Daybell, who was found dead in October.

Woodcock is pleading for anyone with information about the bizarre series of events to come forward to authorities.

“Help us shed light on this,” Woodcock wrote on Facebook. “Someone out there knows something but doesn’t know how all the pieces fit together. Help me connect them with the police so we can bring justice to my brother and the other victims.”