Here is a really interesting article:
"PORTLAND, Ore. - A retired Portland police detective said Wednesday the silence the parents of 7-year-old Kyron Horman have maintained after his disappearance isnt unheard of but its not the norm either."
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Terri Horman, Kyrons stepmother, hasnt been completely silent. She has spent some time on Facebook since Friday responding to posts from friends and talking about her workouts, which is more that Jensen said he finds unusual.
What I know from being an investigator and dealing with parents in tragic situations like this - homicides, kidnappings, stuff like that - they just really couldnt much function other than to sit and wait for us to call, he said.
Jensen said investigators could be asking the Hormans to be silent and to carry on with their lives as normal, but he said in his experience it is extremely difficult for families to be quiet and stay away from a search scene when a loved one, especially a child, is missing.
http://www.katu.com/news/local/96033344.html