Louisville, KY, mother of two Andrea Knabel has been missing for over two years. The 39-year-old private investigator volunteered her time searching for missing persons until she(,) too, went missing on August 13, 2019.

Andrea’s sister, Erin, was among the last people to see Andrea before she vanished. Erin says she carries guilt over Andrea’s disappearance, in part, because she didn’t help Andrea when she showed up at Erin’s home on the night she went missing.

“I don’t think there is anything that can make me feel better about what I did that night,” says Erin. “It’s something that I struggle with every day.”

This episode of Dr. Phil, “Exclusive: Finding Missing Mom, Andrea Knabel,” airs Friday. Check your local listing for air times.

If you have any information about Andrea Knabel’s disappearance or her possible whereabouts, call the Louisville Metro Police Missing Persons Division at 502-574-7120.

The new docuseries “Finding Andrea,”investigates the disappearance of Andrea Knabel. The four-part series begins streaming Friday, October 15, on Discovery+.

WATCH: ‘It Stays With You, 24/7,’ Says Dad Of Missing Woman About The Grief Of Not Knowing What Happened To His Daughter

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