REXBURG, Idaho — The grandparents of two missing Idaho children are offering a $20,000 reward for information about their disappearance.

Larry and Kay Woodcock held a news conference in Rexburg Tuesday morning with KIFI-TV and other news stations to plea for their safe return.

"We hope this will allow one person to simply say, 'I know where they're at,'" said Larry Woodcock.

Joshua Vallow, age 7, and Tylee Ryan, age 17, were last seen in September in Rexburg.

His grandfather refers to Joshua as JJ and said he is a special needs child who is amazing to be around. He was asked if he believed the children are still alive.

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He said that’s the reason for the reward. “We pray constantly that they are.”

Local authorities and the FBI are investigating this case. A missing child report was received on Nov. 26, 2019.

Nearly a month later on Dec. 20, police said in a press release that the children’s lives could be in danger.

Woodcock says the last time he spoke with his grandson was August 10 in a very bizarre FaceTime call.

"The last call was the most awkward call," Woodcock said. "It was like someone was watching him and directing him.  There was somebody else there, holding the device because normally he'd run around with it. 

Investigators believe Lori Daybell, Tylee’s biological mother and Joshua’s adoptive mom, knows what happened to them. She has refused to cooperate with law enforcement. She left town with her new husband Chad Daybell.

Daybell's previous wife, Tammy Daybell, was found dead in October. Police first believed she died from natural causes; however, police now believe her death may be suspicious. Her remains were exhumed from a Utah grave to look for more evidence into her death.

Police say they have received hundreds of tips but have yet to find the missing children. They are asking people to come forward if they have any information.

"We're not promised tomorrow and all I want before I go is just to see those children," Woodcock said.

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