The FBI is seeking the public’s help in the search for two missing children whose mother was extradited back to Idaho from Hawaii Thursday to face felony charges in their September disappearance.

On Thursday, investigators in the bureau's Salt Lake City field office released photos from Sept. 8 that show 46-year-old Lori Vallow along with her 17-year-old daughter Tylee Ryan, and her son, 7-year-old Joshua “JJ” Vallow, at Yellowstone National Park in Wyoming.

The photos were taken on what is believed to be the last day the teenager was ever seen. The boy went missing weeks later on or around Sept. 23, reports say.

In one of the photos from Yellowstone, Vallow appears with Joshua, wearing a dark hooded jacket while smiling happily for the camera.

Lori Vallow and her 7-year-old son Joshua Vallow are shown in a Sept. 8 photo taken at Yellowstone National Park. Joshua, along with his sister Tylee Ryan, have not been seen since September 2019.

Credit: FBI

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Credit: FBI

Another photo released by the FBI Thursday shows Tylee embracing Joshua, with their uncle in the background.

In this photo released by the Federal Bureau of Investigation, 7-year-old Joshua Vallow, his sister, 17-year-old Tylee Ryan, and their uncle, Alex Cox, are shown in Yellowstone National Park on September 8, the last day Tylee was seen alive.
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“An ongoing investigation has determined” that the children were at Yellowstone National Park with Vallow, and their uncle Alex Cox, the FBI said, according to multiple news reports.

The FBI also released two photos of a Ford pickup truck in which the family traveled to the park.

The silver 2017 Ford F150 pickup truck with Arizona license plates that Lori Vallow and her children were seen traveling in during a visit to Yellowstone National Park last September.
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Another view of the silver 2017 Ford F150 pickup truck with Arizona license plates that Lori Vallow and her children were seen traveling in during a visit to Yellowstone National Park last September.

Credit: FBI

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Credit: FBI

On Twitter Thursday, the FBI appealed to anyone who had been at the park that day to search their photos and videos and submit any that show Vallow and the children.

A new booking photo shows Lori Vallow after her return to Idaho on Thursday.

Credit: Madison County Sheriff's Office

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Credit: Madison County Sheriff's Office

For now, Vallow was due in court Friday after she arrived back in Rexburg, Idaho, Thursday afternoon. Reports say she is being held at the Madison County Jail.

Vallow faces two felony counts of desertion and nonsupport of dependent children, among other charges.

Since Feb. 20 she had been jailed in Hawaii on $5 million bond.

Prior to her arrest, reports say she had been living on the island of Kauai with her husband, 51-year-old Chad Daybell, since the couple married in early November.

There were no signs her children were ever with her.

Last week, a judge refused to lower Vallow’s bail after prosecutors argued she was a flight risk. At a status hearing on Wednesday, Vallow's defense attorney Craig De Costa invoked Vallow's Fifth Amendment rights against self incrimination, warning the mother should not be questioned without an attorney present during the trip back to Idaho, according to USA Today.

Idaho mother of 2 missing children arrested in Hawaii

Vallow had been under investigation in the case since the boy's grandparents reported him missing Nov. 25, but Vallow lied to police and vanished from her Idaho apartment just as authorities were preparing to carry out a welfare check, according to reports.

Before she left Rexburg, Vallow reportedly told neighbors she sent her son to Lake Charles, Louisiana, to spend time with his grandparents, which turned out to be untrue, according to investigators.

The apartment complex in Rexburg, Idaho, where the Vallow family lived near Yellowstone National Park.
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Police next announced the children missing in December.

After she resurfaced in Hawaii, police served Vallow with a court order from Idaho that gave her five days to bring the children in front of a judge by Jan. 31, a deadline she missed.

Focus shifts to national park

The focus of the investigation has turned to Yellowstone National Park, not far from the family’s last known residence. Authorities there said they are just waiting for the snow to melt to be able to search the grounds that cover nearly 3,500 square miles.

Officials said the photos taken on Sept. 8 at Yellowstone were found on Vallow’s iCloud account, according to news reports, citing recently filed court documents.

Joshua was last seen on a neighbor’s doorbell camera playing in the yard with a friend outside the family's apartment in Rexburg on Sept. 17. A week later, on Sept. 24, reports say Vallow withdrew Joshua from his elementary school and he was never seen again.

USA Today reports that Joshua’s school and two property owners in Hawaii were recently subpoenaed to appear in an Idaho court on March 9 and produce documents related to the case.

Police in Rexburg said Vallow never reported the children missing and never cooperated with their investigation.

Vallow’s Hawaii lawyer claimed she did not produce the children because she did not want them to go into foster care, according to The Daily Beast.

3 suspicious deaths

Her arrest on Feb. 20 was the culmination of months of efforts by federal, state and local agencies working around the clock to find the children and to explain three other suspicious deaths connected to the case.

Vallow married Daybell only two weeks after his previous wife of 30 years died in October, police said. Tammy Daybell's body has since been exhumed for an autopsy, reports said.

Lori Vallow's husband, Chad Daybell, has not been charged in the case.
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Two months later, in December, Lori’s brother Alex Cox also died of unknown causes, according to reports. Cox, who appeared in the Sept. 8 photos at Yellowstone, claimed self-defense in the July 2019 shooting death of Lori’s previous husband, Charles Vallow, and he was never arrested or charged. Reports say Arizona authorities are now investigating Cox’s death.

Daybell, an author of several novels about near-death experiences and the apocalypse, reportedly developed a relationship with Vallow while she was still married.

According to Fox News, members of Vallow’s extended family told local news media that Vallow joined a “cult” with Daybell in preparation for the end of the world.

Before his death, Charles Vallow filed for a protection order against Lori after she allegedly began making threats to kill him. He confided to family members that Lori was cheating and claiming to be a god, according to The Arizona Republic. He was in the process of filing for divorce when he was killed, according to news reports.

Daybell is not facing any charges in the case and maintains that he and Vallow have done nothing wrong.

Reports say last week he told news media in Hawaii that “the kids are safe,” according to a report in the Huffington Post, citing ABC News.

A wide-ranging investigation is continuing.