When a seven-year-old girl vanishes while playing outside in a southside Tucson neighborhood,

her disappearance is disturbingly similar to the abduction and murder of another child that occurred a year prior.

Investigators are haunted by two unsolved cases they believe were likely committed by the same predator in this episode of Last Seen Alive.

Thanks for listening to Last Seen Alive. I'm your host, Leah, crime analyst by day and true crime storyteller by night.

As always, I'm your coach. Scott.

A quick heads up. This episode is about the disappearance of one child victim and the murder of another.

It contains discussion of crimes against children, including sexually motivated crimes. We won't go into any graphic detail, but still, please listen with care.

Karen Grejeda was last seen alive on January 11, 1996. She was seven years old at the time and

lived in Tucson, Arizona, with her mom and little sister at the Saguaro Crest Apartments in the city's south side, specifically the Sunnyside neighborhood.

Karen's dad, a fisherman by trade, lived in Guaymas, Mexico, so it was just Karen, her mom, little sister, and a roommate in Tucson.

Their apartment complex was popular with families with young children, a fact that was immediately

apparent to anyone who visited.

According to what another parent told the Tucson citizen, there was always a large group of

kids playing in and around the complex's courtyard.

On the evening of January 11th, a Thursday, Karen was, as she so often was,

one of those many children. Earlier, she'd ridden her bike before taking a break to play some video

games. Then she'd headed back outside with her five-year-old sister, Alejandra, to play a little

longer until dinner was ready. They'd gotten caught up and playing with the other kids, and at some point, they'd become

separated.

When the girl's mom, Rosalba, called them inside for dinner.

Only Alejandra responded.

Karen was nowhere to be found.

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