Unsolved: DNA identifies killer of 12-year-old Lesia Jackson, murdered in 1979

CONROE, Texas (KTRK) -- On September 7, 1979, Lesia Jackson, 12, spent most of the day swimming with her older brothers at Lake Wildwood off FM 1485 in Conroe. Life was carefree for the Washington Junior High student.

When her brothers were ready to go home, Lesia wasn't. They started walking without her. Lesia eventually followed and she was last spotted walking alone on Creek Bend Street towards home.

That was the last time anyone saw Lesia alive. Her body was discovered a week later.

The little girl's death was one of the highest-profile unsolved murders in Montgomery County, until now.

The Montgomery County Sheriff's Office says they used new DNA technology to identify Lesia's killer. Gerald Casey, newly ID'ed as the girl's killer, was actually executed 10 years after the girl's death, for another murder case.

The sheriff's office says this is the oldest cold case murder their department has solved.

In 2018, ABC13's Courtney Fischer researched Lesia's murder and featured the cold case details as they had never been covered before. She was able to share photos and details that had previously been held back from the public, as detectives chased down leads.

You can watch that full report in the video player below.

Details public for 1st time in rape and murder of 12-year-old

At that time, Courtney reported that Lesia's mother and brothers have since moved away from Texas. We talked to one of her brothers about the case. Family members declined to do an interview saying it's just too painful to talk about what happened that day. That brother says Lesia's family forgave the killer many years ago, saying it's the only way they could keep living.

For more on the Unsolved series, follow Courtney Fischer on Facebook, Twitter and Instagram.

Share your loved one's story with ABC13's Courtney Fischer here.

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