The FBI has released a new photo of “cult” mom Lori Vallow's daughter, taken the day the teen was last seen six months ago.

The photo's release Thursday came as Vallow was flown from Hawaii to Idaho, where she faces child abandonment charges in the disappearance of her daughter, Tylee Ryan, 17, and her son, Joshua "JJ" Vallow, 7. She is due in court Friday.

The photo from the FBI shows Tylee holding JJ, who has autism, at Yellowstone National Park in Wyoming on Sept. 8.

The FBI on Thursday also released a second photo taken that day at Yellowstone showing Vallow, 46, with JJ.

Idaho police say Tylee hasn't been seen since the trip to Yellowstone, and that JJ hasn't been seen since Sept. 23.

"An ongoing investigation has determined" that on Sept. 8 Tylee and JJ were at Yellowstone National Park with Vallow, and their uncle Alex Cox, according to the FBI.

Agents said Vallow, Cox and the children traveled there in a Ford pickup with Arizona plates. The FBI made available two photos of the pickup.

The FBI is seeking any photos and video that may show Vallow, Tylee and JJ at Yellowstone.

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Vallow arrived in Rexburg, Idaho, Thursday afternoon. She has been held on a $5 million bond since her arrest in Hawaii last month.

A reporter from East Idaho News was at the airport and peppered Vallow with questions about the missing children before deputies drove her away.

Vallow refused to say anything, the news outlet reported.

Rexburg police said the disappearance of Tylee and JJ was related to the suspicious death in October of Tammy Daybell, whose husband, Chad Daybell, 51, married Vallow two weeks later.

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Arizona police also are investigating the death of Cox in December. Five months earlier Cox fatally shot Vallow’s estranged husband Charles Vallow in what Arizona police called self-defense.

Members of Vallow’s extended family have been quoted by local media saying that Vallow joined a “cult” with Daybell, a self-proclaimed Latter-day Saint known for his religious books detailing the end of the world.

Many of his books deal with doomsday situations or near-death experiences, including his own, according to reports

Daybell and Vallow were affiliated with Preparing with People, a group that says its mission is to “help prepare the people of this earth for the second coming of Jesus Christ.”

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The group has denied accusations it is a cult.