Tonight on Date Live.

It was a young female.

She had a high school graduation ring on.

I promised Courtney, nearly on her grave, I'm going to find out what you're here for.

We ended up getting a anonymous phone call saying, followed a money.

I polygraphed 456 different guys.

When they asked you, did you kill Courtney?

I said no, I didn't kill my sister.

I told Stephanie that day I saw him solve his case on the diet trying.

He was going to open his podcast up for tips.

Everybody walked the stuff so to real life, real ground.

The hotline was blowing up.

I get a phone call saying, her ex-husband knows who did it.

He returned home in the middle of the night smelling of death.

You're about to tell them the answers.

All the more crying, they're blown away.

You must have just felt such betrayal, yes ma'am.

I was floored.

A teenage girl is found dead.

Her family's long fight for justice reveals a dark secret.

I'm Lester Holt, and this is Date Line.

Here's Andrea Canning with Who Killed Courtney Coco.

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