Saturday marks 30 years since a crime that stunned the city of Stamford--the brutal murders of a young mom and her infant.

"This is a haunting case," said Stamford Police Capt. Doug Deiso.

"I think it impacted everyone from the community and everyone in my office and especially at this police department," added Stamford State's Attorney David Applegate. Decades later, the unsolved murders of 18-year-old Rhonda Johnson and her 6-month-old son, Coran, still do because of the shocking violence.

On Sept. 12, 1996, Johnson was found slumped over the wheel of her family's car on Grenhart Road. Her son was still strapped into his car seat in the back. Both had been shot in the head.

"It completely doesn't make sense," Deiso said.

"She never got into trouble. She did everything right. She was working. She was going to school. She was raising her son," Applegate told News 12.

Johnson had recently graduated from Westhill High School. She was taking classes at Norwalk Community College and working part-time at Stamford Hospital, building a future for her and her child.

"Coran was the joy of her life, and we were just one big, happy family when the baby was born," said her mom, Blanche Johnson-Young.

On the day in question, Johnson followed her normal routine, picking up her son from the babysitter before heading to her job. But she never made it there.

"After she didn't show up to work--and that wasn't like her--I started looking for her," Johnson-Young recalled, sharing how her concerns grew as it got later.

Then came a call from a friend.

"She said, 'Just tell me what your license plate number is,' and I said, '455FXJ,' and she said, 'Oh my God,' and that's when I knew something really was wrong," Johnson-Young told News 12. "It was horrible. It was horrible."

Even worse has been waiting three decades for an arrest despite investigators' efforts. The case has been re-examined multiple times over the years, including in 2015 by the Connecticut Cold Case Unit out of the Chief State's Attorney's Office. Applegate was part of that team that spent over a year going back over it.

"I spent my first nine years as a prosecutor here in Stamford and had been aware of the case because of how serious it was," Applegate explained. "And then in 2015, I transferred to our division's Cold Case Unit."

But despite that work, the case remained cold. It's one reason why Applegate returned to the Stamford State's Attorney's Office over the summer, now as the top prosecutor.

"It felt like real unfinished business for me when I left the Cold Case Unit," he told News 12. "I wanted to come back for Rhonda Johnson and Coran Johnson, to make another effort at solving this."

Police aren't giving up either, especially with advancements in forensic testing.

"The technology behind it has come light-years. We have sent items up to the state lab that were specifically found in the vehicle to be reviewed. And we're hoping that will provide some answers for us," Deiso said.

But police are also turning to the public.

"We know we can't do this alone," Deiso stated. "The communities of Stamford have always shown up when we needed them to help us solve cases."

Investigators are hoping that now that there are anonymous ways to submit tips, unlike in 1996, people might be more willing to speak up.

"I think that there are people in this community who have more information that could help us," Applegate said. "It could be the missing piece we need."

"Just come forward if you know something," pleaded Johnson-Young. "I'm crying out for justice for my children."

On Thursday, ahead of this weekend's grim milestone, she returned to her daughter's and grandson's gravesite with friends and investigators by her side. The hope is this is the year she'll finally have closure.

"I have faith in God, and I know God knows. And one day I'll know. I gave it over to the Lord. That's all I can do and just hold their memories right here," Johnson-Young said, pointing to her heart.

There's a $50,000 reward for information leading to an arrest and conviction in this case.

Anyone who knows something is asked to reach out to the Stamford Police Department Major Crimes Unit at 203-977-4418.

Tips can also be submitted anonymously by calling 203-977-TIPS or texting TIP411.