Karla Rodriguez, 7, Disappeared During Bike Ride in 1999 — Why Parents Still Think She’s Alive

It wasn’t unusual for Karla Rodriguez to ride her bike through her Las Vegas neighborhood and stop off at friend’s house – sometimes staying the night.

So when the 7-year-old girl didn’t return home on Oct. 20, 1999, her father Ramon Rodriguez assumed she was staying with a friend.

But the following morning, her mother, Elia Zepeda — who’d been working late the night before — learned her daughter hadn’t shown up for school, and her heart sank.

“I sensed something was wrong,” she told PEOPLE in the current issue, which is on newsstands now. She added that this feeling was something only a mother could know.

It has been 20 years since the couple’s daughter vanished, yet they continue to hold onto hope that they will be reunited. They are grateful for everyone’s interest in the case, including the police who have never given up.

Dan Long, a homicide cold case investigator with the Las Vegas Metropolitan Police Department, grew up in the same neighborhood as Karla and is very familiar with the case. He and his partner, he says, are taking the case apart and checking for new ways to look at it.

“Back then, they weren’t looking at DNA the way we look at DNA now. That’s our major focus,” he says. “We’re looking for anything that could lead us to what might have happened.”

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At the time, there was a massive search for the girl, he recalls. Command posts were set up at the school and the girl’s home, volunteers scoured the area, and bloodhounds were brought in. Long says a deputy chief, two detectives from the missing persons unit, and special agents from the FBI have since retired, but they agreed to return and help out.

“Those are the best eyes for this,” he says. “They are going to tell us what their feelings were … and then we’re going to chase everything down the best we can.”

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Meanwhile, Karla’s parents have kept her favorite doll, her clothes and homework because these are the only memories they have of their daughter – for now.

Says Zepeda, “I know I’ll see her again.”

Call Metropolitan Police at 702-828-3521 with information about Karla Rodriguez.