When 7-year-old Kyron Horman vanished without a trace in 2010, his stepmother, Terri, the last known person to see him, was accused by his mother and father of being involved in his disappearance.

WATCH: Terri Horman Describes The Last Time She Saw Stepson Kyron Horman Before He Disappeared

Despite remaining under a dark cloud of public suspicion, Terri was never named by law enforcement as a suspect in his disappearance and she adamantly denies any wrongdoing. Watch her story here.

In the video above, Kyron’s parents, Kaine and Desiree, who appeared on Dr. Phil three years ago, explain why they believe Terri is hiding crucial information that could lead them to finding their son. And, Terri explains why she lied to the media shortly after Kyron’s disappearance.

Watch more from this show here. And on Thursday, Terri, who failed two polygraphs, answers questions about what some have alleged was suspicious behavior in the days and weeks following Kyron’s disappearance. Check here to see where you can watch.