Mental health experts say uncertainty in missing persons cases can deepen trauma and hinder grieving.
When a loved one goes missing, relatives can feel guilty simply for eating, says Charlie Shunick, whose sister was kidnapped.
Various Supreme Court cases have ruled that evidence found by bloodhounds is admissible in court.
It has been 30 days since 84-year-old Nancy Guthrie, mother of TODAY show co-host Savannah Guthrie, was kidnapped from her Catalina Foothills home.