I'm Lester Holt. Tonight on Dateline, a young woman goes missing on a North Dakota reservation.

Her aunt will stop at nothing to find her.

Her father always told me to keep an eye on her.

You had made a promise to him?

Yeah.

To make sure she was okay.

I was gonna find her.

You just knew as her mom that something was very wrong.

Yes, I did.

There was a report that she'd been in in like a silver car.

I knew that she was probably in trouble.

You get a call from a blocked number.

Yes.

You need to get honest with me because I'm done playing.

Well, I bet I only honest with you.

She would kind of turn it on and try to get some truth out of it.

I'll keep digging and digging.

There are so many unsolved cases out there.

Indigenous women and girls across the nation, a tired red chain,

to really think about how we are invisible.

I don't want another family to ever feel like how we felt.

Here's Andrea Canning with, the secrets of Spirit Lake.

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