Tonight on Dateline.

She was really looking forward to creating her own family.

We tried our best.

And sorry it wasn't enough.

Because if it was, she would be here.

They found Sandra deceased in her apartment.

I was told that she had committed suicide,

but in the back of my mind, it isn't adding up.

Given how excited she was about becoming a mom,

it didn't jive with us.

This broken necklace.

This was a clue to you.

Definitely, yeah.

I said that sounds like a sign of a struggle.

When I first saw the video, my jaw dropped.

He's walking into the apartment. He has a mask on. He's got a hoodie on over his head.

I'm thinking somebody murdered her. You're thinking cover up? Definitely.

Your investigation revealed a bombshell.

Yes, it did.

Wherever that let us, we would go.

A young mother-to-be murdered.

Who was behind it?

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