Gillie, 51, a wife, and mother of six, was leaving Gospel Center Church off N. Driver Street when she was gunned down inside her car.
More than 30 years later, Gillie's family is bracing for the 51-year-old McDowell's release, planned for September 21.
"Really is a bit of a head scratcher for me as an American citizen. This man murdered my mother," said Scott Gillie, Doris' oldest son. "I don't know what the specific rule is that allows him to even be eligible for parole."
A legal error forced the courts to change his death sentence to life.
Under North Carolina Fair Sentence Law, life sentences before October 1994 are eligible for parole every few years.
In an exclusive interview, Scott Gillie told ABC11 that the family has been fighting for 18 years to keep McDowell in prison.
In the decades after Gillie's murder, her family has grown to 23 grandchildren and 13 great-grandchildren.
"I've thought about my mom every day since it happened. So now I will be thinking about him and he's free, and her for the rest of my life." Scott Gillie said. "She would have forgiven him, but if he had known her, there's no way he would have done what he did."
Scott Gillie said he has forgiven McDowell. But he has no desire to meet him or speak to him.
The parole board meetings are private, so it's not known what factors played into its decision to release McDowell.
McDowell had accumulated 40 prison infractions during the years for offenses including fighting, faking illness and disobeying orders, but the last incident was in 2002, according to inmate records obtained by The Associated Press.
In the early 1990s, Structured Sentencing law was passed by lawmakers. That law prevents convicted murderers from receiving a parole hearing.
Asked whether the justice system failed his mother, Scott Gillie replied: "Yeah. Absolutely."