New surveillance footage might give investigators fresh clues into the disappearance of two Idaho kids. The video appears to show their mother, Lori Vallow, at a storage facility near their home shortly after 7-year-old JJ and 17-year-old Tylee Ryan were last seen in September.

Investigators went through a storage unit where they found bikes, photos and a backpack with JJ's initials, according to CBS News' Jonathan Vigliotti who reported from inside the Rexburg, Idaho facility.

"It was disturbing to see that it was the children's belongings that were in that storage unit," private investigator Rich Robertson said. Robertson had been working on the case with JJ's grandparents, Kay and Larry Woodcock.

The video shows Vallow and a man visiting the storage unit on multiple occasions after the children went missing in Fall 2019. At one point, a man is seen carrying a heavy tote bag.

"If they had expected the kids to be coming home soon, why would that stuff be in a storage? On the other hand, if they didn't think the kids were ever coming back, why keep it?" Robertson asked. Vallow and Daybell have both denied any wrongdoing in the case.

Kay Woodcock attended a press conference last week after Vallow ignored a court order to produce the two kids. On Wednesday, the Woodcocks filed a petition to obtain guardianship of JJ.

Meanwhile Vallow and her husband, Chad Daybell, were last seen in Hawaii at the end of January after both of their former spouses, and Vallow's brother, all died under what authorities call suspicious circumstances over the past eight months.

Robertson, the private investigator working with JJ's grandparents, said that one of the victims, Vallow's ex-husband Charles, had a $1 million life insurance policy.

"At this point we think that Lori Vallow believed she was the beneficiary," he said.

A legal expert who spoke to CBS News said that a lack of evidence could be why Vallow has not yet been arrested. A contempt charge for failing to produce the children as the court ordered could be a possibility, though it is likely insufficient to compel her back to Idaho.