A mother-of two who was charged in October in the 25-year-old killing of a “romantic rival” is the focus of Friday’s episode of Dateline.
Carolyn Heckert, 48, was arrested in the death of Sarah Jo DeLeon, whose body was found stabbed to death near railroad tracks in Kansas City, Kansas, in 1989.
DeLeon’s mother, Gail Elieson, wasn’t sure her daughter’s case would ever be solved. “I was living with that,” she tells Dateline. “That we would never know.”
In 2014, the case was reopened when investigators conducted forensic technology tests, hoping for a break in the case.
Kansas City Police Department’s Maj. Curtis Nicholson tells PEOPLE that DeLeon’s family was a driving force in their investigation.
“They lost their loved one,” he says. “They help keep you focused. They help keep you moving on when sometimes things get rough, or sometimes when you’re not getting the results that you want, they help keep you going down the road. This family was very involved from day one.”
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Since the investigation is still ongoing, Nicholson said he could not discuss specifics, such as evidence or what lead them to arrest Heckert, a businesswoman.
Heckert has pleaded not guilty. In January, her bond was reduced from $1 million to $500,000, according to a report in the Kansas City Star. If she posts bond, the judge ordered her to be placed on house arrest and she must hand over her passport.
A preliminary hearing is scheduled for April 7. It was not immediately clear if Heckert has retained an attorney.
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Still, there are many unanswered questions. In the course of the investigation, officials believed they linked DeLeon’s case and another death in nearby Independence, Missouri.
In January 1994, Diana Ault was shot to death inside her home while her 4-year-old son and 8-month-old daughter were left unharmed. Investigators have long suspected that the two deaths were linked, but didn’t have evidence. No one has been charged in connection with Ault’s death.
Dateline speaks with family members from both DeLeon’s and Ault’s families.
The episode airs Friday (10 p.m. ET) on NBC.