As the mother of two missing children faces a judge in Idaho Friday, the FBI is looking for anyone who may have seen the family at Yellowstone National Park on September 8. Investigators said the last known image of 17-year old Tylee Ryan was taken on a family trip to the park that day.

Police say the photo of Ryan with her 7-year-old brother Joshua "JJ" Vallow and her uncle Alex Cox was recovered from her mother Lori Vallow's iCloud. Another image released by investigators shows Lori and JJ.

Now the FBI hopes one of the thousands of tourists that visited the park on September 8 captured photos of the family, CBS News correspondent Jonathan Vigliotti reports. The agency also released images of a white Ford pickup truck the family was believed to be traveling in and asked to talk with anyone who saw it.

 

The last known images of JJ came a week after the trip to Yellowstone back in Idaho. He is seen running in a yard on doorbell camera footage.

Investigators are also looking into Cox after a series of mysterious deaths, including his, sources told CBS News. He was seen on a police body camera after fatally shooting Vallow's ex-husband in July.

Sources said investigators believe Cox is also linked to the mysterious death of Tammy Daybell in October. Days after her death, her husband, Chad, married Lori Vallow. Cox then mysteriously died in December.

Lori Vallow is scheduled to be in front of a judge at 2 p.m. local time in Idaho. It will be the first time in months she will be in a room with the children's grandparents, who had asked for a welfare check that set the investigation into the whereabouts of the children in motion in November.

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