PORTLAND, Ore. -- KGWhas learned that Kyron Horman's parents and step-father all passed polygraph tests conducted by police during the investigation into the boy's disappearance, according to a reliable source.

In a lengthy statement Monday evening, the parents of Kyron Horman answered a number of questions submitted via the media about their seven-year-old son's disappearance and the investigation.

In that statement, Desiree Young, Tony Young and Kaine Horman said they had all taken polygraph tests. They later added that all three of them had passed the tests.

Kyron has been missing for more than a month now.

We remain hopeful because we haven't been given any information by law enforcement to indicate he isn't still alive and therefore we will always expect that he will come home to us, their statement also said.

READ:Complete family statement, 7/5

KGWpreviously learned that Terri Moulton Horman, Kaine's estranged wife and Kyron's step-mother, had taken at least two lie-detector tests and the source said that police believe she was withholding information.

Desiree and Kaine declined to comment on reports Sunday that Kaine had been told by investigators that Terri had tried to hire a landscaper to kill him. Kaine moved out of thehouse with his young daughter and filed for a divorce and restraining order against Terri shortly after he was reportedlyinformed of the plot.

In the latest statement, Kyron's parents also reiterated their claim that Terri has not been cooperating fully with investigators.

Based upon information we have received from briefings it is our understanding, and continues to be such, that she has not been cooperating, the statement read. We continue to issue our plea of her FULLY cooperating with law enforcement and the investigation to help bring Kyron home as quickly as possible.

However, Kyron's parents emphasized they did not want the focus to shift to Terri.

Our main goal is to keep Kyron in the front of everyone's minds because we have a better chance of finding him, they said. So we are constantly working to keep him the focus of the story and not Terri.

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