In the early morning hours of October 13, 2018, 16-year-old Karlie Gusé went missing from her home in rural Mono County, California, and seemingly vanished into thin air.

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Karlie’s father, Zac, and stepmother, Melissa, were with her the night she disappeared.

WATCH Dad And Stepmom Of Missing Teen Karlie Gusé Explain Why They Didn’t Share A Recording Of Their Daughter’s Last Night At Home With ‘Dr. Phil’ Producers

Melissa claims that before she went missing, Karlie admitted to smoking marijuana and was acting “very strange.” She says she stayed up with Karlie most of the night, before falling asleep around 5:45 a.m. When she woke up at 7:15, Melissa says Karlie was gone.

“Law enforcement are treating Karlie’s disappearance like a runaway case,” says Zac, adding, “It’s really hard for me to believe that, because she would have contacted us.”

Continuing, he says “One of the hardest things with this is having zero – zero – answers.” Zac and Melissa are adamant that they have no idea what happened to Karlie, or where she could be.

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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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Stepmom Of Missing Teen Karlie Gusé: ‘I Had Spent The Whole Night With Her In Her Room’