David Muir

And that shell casing actually made its way into the floor drain.

The fact that Amy had a .380 and a .22, that she was shot by two different weapons, still remains a very intriguing piece of this case.

Logically, you'd think two people, or at least two people.

Why would you have two guns?

So that was the working theory that it was more than one person.

It was a very limited amount of resources back in 1991 to devote to this case.

We're talking about a six-man homicide unit.

So they were stretched thin from the very beginning.

Austin in 1991 was kind of a sleepy college town.

A third the size of it is now.

And people back then didn't lock their doors at night.

It was just small.

But when the yogurt shop murders took place,

It changed Austin forever.

The yogurt shop murders have been repeatedly described as the day Austin lost its innocence.

My sister was very social, energetic.

She was really into fitness and fashion and, you know, had fantasies of modeling and doing lots of different things.

The youngest of the girls was 13-year-old Amy Ayers, still an eighth grader.

And like her parents and big brother Sean, little Amy was a rancher at heart.

So in December 1991, it was a cool evening.