A 12-year-old girl is murdered in her own home.

And the case stalls when investigators find little forensic evidence at the crime scene.

But scientists also know that criminals unknowingly take evidence with them as they leave a crime

scene.

And in this case, the killer left with the genetic fingerprint of his victim.

In between two of Minnesota's 10,000 lakes is the small town of Wasika, a quiet community

with virtually no violent crime.

Not far from the shores of Loon Lake was the home of Connie Larson and her three daughters.

They're all like five and four years apart, but they are very close.

They were never apart and they just adored each other.

Callie was definitely the baby of the family.

And she was daddy's little girl.

A 12-year-old Callie Joe was in the seventh grade and loved gymnastics.

She was good.

I think because she just loved it and she put a lot of energy into it.

After school on April 20, 1999, Callie Joe got off her school bus and walked down this

path towards home just as she always did.

Callie Joe was the first one home that day.

Her mother and sister were expected later.

The rule in the family was everyone needed to be home and no visitors at five o'clock

because that's when I arrived home and then we had our family time.

Sixteen-year-old Jamie was the next family member to arrive home.

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