(CNN) -- Paula Cooper was just 16 years old when she became the youngest person on death row in the United States. That was in 1986. On Monday, after 27 years behind bars, Cooper walked out of Indiana's Rockville Correctional Facility a free woman. She emerged around 10 a.m., said Douglas S. Garrison, chief communications officer for the Indiana Department of Corrections. Cooper had an unlikely ally supporting her release: Bill Pelke, the grandson of the woman she killed. The events that ensnared both families started when Cooper was 15 and devised a plan to steal money with her friends.
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NEW: Cooper "would take it back in a heartbeat if she could," victim's grandson says
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Paula Cooper was 16 years old when she was sentenced to death for murder
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She stabbed 78-year-old Bible teacher Ruth Pelke in the stomach and chest 33 times
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Victim's grandson: I realized forgiveness had taken place, and it brought healing to me
"I became convinced beyond a shadow of a doubt that my grandmother would have had love and compassion for Paula Cooper and her family," @placeholder told CNN.