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Story highlights

James Renner vowed to find Amy Mihaljevic's killer when he was 11

He uses the Internet and social media to crowdsource leads in the case

Editor’s Note: Do you have information about the disappearance of Amy Mihaljevic? Call the Cleveland FBI at 216-522-1400 or contact your local FBI field office.

(CNN) —  

James Renner was 11 years old when Amy Mihaljevic was kidnapped from a shopping plaza in Bay Village, Ohio, in 1989.

As he describes it, he “fell in love” with the 10-year-old girl whose class picture appeared at the top of TV newscasts for weeks after her abduction. He was also terrified of the mystery man who snatched her in broad daylight, right across the street from the Bay Village Police Department.

He vowed to find her killer.

“Everybody has