Paula Cooper of Gary was 16 in 1986 when she and three other girls were convicted in the 1985 stabbing death of Ruth Pelke, 78, during a robbery.
The state Supreme Court commuted her death sentence in 1989 and gave her a 60-year prison term.
The Indianapolis Star reported Saturday Cooper, now 43, will walk out of the Rockville Correctional Facility a free woman Monday.
The newspaper said Cooper declined a request for an interview and her plans for her future were unclear.
Corrections Department spokesman Douglas S. Garrison said Cooper will leave prison with at least $75, a new outfit provided by the state and a bachelor's degree, the Star said.
Bill Pelke, a grandson of Cooper's victim, has forgiven her and is now a friend.
"My main concern is seeing her get settled and find a job," he said.
Rhonda Labroi said her sister "has paid her price" and is "a very different person" now.
"She is a lot more educated and older and wiser now. I think things will be different," Labroi said.
"There are second chances. It seems like God has given her another chance. I think if people give her a second chance, she'll do fine."
Cooper expressed remorse during a 2004 interview with the Star.
"Everybody has a responsibility to do right or wrong, and if you do wrong, you should be punished," she said. "Rehabilitation comes from you. If you're not ready to be rehabilitated, you won't be."
Indianapolis attorney Jack Crawford, who prosecuted Cooper, wishes her well.
"She has served her time, and perhaps she can make some contributions to society," he said. "I hope she continues to try to rehabilitate herself and make some amends for the crime she committed some 30 years ago."
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