Pregnant mom and 6-year-old son found dead in a trailer. Nearly 20 years later, the case remains cold.

A pregnant mom and her 6-year-old son were murdered inside their Alabama home. Nearly two decades later, police still have yet to arrest their killer.

On Sept. 16, 2002, Monica Faye Pritchett Rollins, 23, and her son Dalton Scott Rollins, 6, were found by a relative after the two had been killed in their Heflin, Alabama, home, according to the Alabama Attorney General’s Office.

Monica was 36-weeks pregnant when she was killed and the fetus died, according to the attorney general’s office.

Monica’s other son, who was 2 years old at the time, was also in the home but unarmed, officials said.

Heflin police chief A.J. Benefield told AL.com in 2014 that he was a responding officer when the murder happened in 2002.

"So really, there's three victims," Benefield told AL.com. "It was the worst crime scene I've ever seen. Not a day goes by that we aren't talking about this or working on it in some way. It's very near to our hearts."

The news organization reported police have released few details about the murder, including how the family died. The chief said that was to help eliminate false confessions over the years.

"There are certain things that only the killer would know about this case, outside of those who are familiar with it," he said, according to AL.com.

The family lived at their trailer for about a year when they were murdered, AL.com reported. Police said the mom and son had been dead for several days when the relative went to the home after not hearing from them.

Now, 20 years later, police have still yet to make an arrest in the murders. Anyone with information on the cold case is asked to contact investigators at (866) 419-1236.