Zac and Melissa say Zac’s 16-year-old daughter Karlie, vanished from their home in the early morning hours of October 13, 2018. They reported her missing to the authorities who searched their neighborhood and the nearby desert for days.

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Melissa also began posting livestream videos to Facebook to find Karlie, but says after several days, people started calling her a murderer.

WATCH ‘People Started Calling Me A Murderer,’ Says Stepmom Of Missing Teen Karlie Gusé

Both Melissa and Zac adamantly deny having anything to do with Karlie’s disappearance.

“Best case scenario, she ran away, and she’s safe,” says Zac. Both he and Melissa say they believe someone may have taken their daughter.

Why does Karlie’s mother, Lindsay, say she’s convinced Zac and Melissa know more about the teenager’s disappearance than they’re admitting?

WATCH Dr. Phil Advises Guests To Put Aside ‘Personal Agendas’ And Focus On Finding Their Missing Daughter

Check here to find out where you can watch part one of this two-part Dr. Phil airing Monday.

If you have any information about the disappearance of Karlie Gusé, please call the Mono County Sheriff at 760-932-7549. Choose option #7.

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Dr. Phil Advises Guests To Put Aside ‘Personal Agendas’ And Focus On Finding Their Missing Daughter