Desiree Young, whose son Kyron Horman vanished from a Portland school four years ago and has never been seen since, says the boy's stepmother Terri Horman failed three lengthy polygraph tests when questioned by investigators about the boy's disappearance.
Terri Horman quickly became a focus of the investigation into Kyron Horman's case, but police have still not made any arrests since starting the search for Kyron Horman on June 4, 2010.
Desiree Young, Kyron Horman's biological mother, said her mission is to keep the pressure on Terri Horman by sharing new details about the case, and she shared these new details without the blessing of investigators.
"They might be upset with me. And you know, I would like them to sit in my shoes and walk the walk and be here four years later," she said.
In the days following the 2010 disappearance of the 7-year-old boy after a school science fair, both sets of Kyron Horman's parents took polygraph tests.
Young said her polygraph session started with these four questions:
Do you know where Kyron Horman is?
Were you with Kyron after 8:45 in the morning?
Do you have direct involvement or any indirect knowledge of Kyron's kidnapping?
And again, do you know where Kyron Horman is?
Young said Terri Horman "failed a lot of questions that they asked her," and that she failed three polygraph tests, each nearly 10 hours long.
"She was saying what her response was and trying to justify what her timeline was and trying to justify why she failed that question," Young said. "That is a glaring example of someone who's guilty."
Terri Horman still lives with her parents in Roseburg. A flier bearing Kyron Horman's face is posted in the front yard.
No one answered the door at the home when a FOX 12 reporter attempted to make contact with her.
Young and her supporters have visited the home to protest Terri Horman's continued silence.
"She still hasn't told us where she was that day and why she's unaccounted for for about two hours of time," she said.
Young is also holding car wash fundraisers to pay for independent searchers like one that took place last fall. She knows resources are stretched thin, but she's frustrated with Multnomah County investigators.
She claimed the sheriff's office turned away offers for outside help, but a sheriff's office spokesman said that's not true.
"When you get egos involved and you start not accepting help from other agencies because your ego might get bruised if they solve the case, you're shooting yourself in the foot," Young said.
Young said four years without answers and without her son have been a nightmare, and she refuses to be in this same position in another four years.
"They're not going to prosecute Terri until they find Kyron. And that's why it's my mission. I am going to find answers. I am going to find Kyron if I have to do it myself," she said.
Terri Horman has never been charged in the case or even called an official suspect.
Multnomah County officials said Kyron Horman's case is still active and they cannot comment on it.
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