2 Idaho children have been missing since September. Their stepfather's ex-wife is dead. There could be a link, police say

Kristin Lam | USA TODAY

Show Caption Hide Caption Missing Idaho children could be linked to a suspicious death Investigators believe the disappearance of Joshua Vallow and Tylee Ryan is linked to the suspicious death of their stepfather's ex-wife.

A possible connection between the disappearance of two Idaho children and a suspicious death has prompted police to ask for help in locating a newlywed couple wanted for questioning.

The Rexburg Police Department is seeking Lori Vallow, the mother of the two missing children, and Chad Daybell, whose ex-wife was found dead Oct 19.

Investigators conducted an autopsy on Tammy Daybell earlier this month, police said in a news release, after initially believing she died of natural causes in her home. During the suspicious-death investigation, authorities also began looking into the disappearance of Joshua Vallow, 7, and Tylee Ryan, 17.

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“Investigators determined that within a couple weeks of Daybell’s death, her surviving husband, Chad Daybell, had married Rexburg resident, Lori Vallow, who is the mother of the missing children,” the release said.

Police spoke with Lori Vallow and Chad Daybell on Nov. 26 while attempting to do a welfare check on Joshua, who is adopted and has special needs. The couple told police the boy was staying with a family friend in Arizona, the release said, but police discovered that wasn't true.

When investigators used a search warrant at the couple's home the next day, police said they determined the couple "abruptly vacated their residence and left Rexburg." Police do not believe they took the boy with them, and authorities asked for the FBI's help in finding him.

Further investigation revealed Joshua and his sister have not been seen since September, police said. Anyone with information is asked to contact Rexburg Police at (208) 359-3000 or a local FBI office.

“We’re working very hard to find more information and to follow up everything that we can,” Fremont County Sheriff Len Humphries told the Idaho State Journal.