Andrea Knabel volunteered her time searching for missing persons until she, too, disappeared in August 2019. The 39-year-old mother of two has not been seen by her family and friends for over two years. Andrea’s father, Mike, and her sister, Erin, say they will never stop searching for Andrea even though it has taken a toll on their family.

“It stays with you, 24/7,” says Andrea’s father, Mike, describing his feeling of being frozen in “permanent grief” from not knowing what happened to his daughter.

Erin, who reported her sister missing, and who was among the last to see Andrea before her disappearance, says, “I think maybe someone might have taken advantage of her that night.”

And later, why does Erin say she carries “a lot of guilt” over her sister’s disappearance?

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 first two episodes will stream on Discovery+ on Friday, October 15.

WATCH: Retired Detective Says Andrea Knabel Disappearance Is ‘The Most Complicated Case I’ve Ever Been Involved In’

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