CATAWBA COUNTY, N.C. — It's a true murder mystery with an unexpected family twist.

A man was killed in a hit and run, and no evidence was left behind. But the woman fighting to get his case solved is not who you’d expect.

Diane Bridges spent 30 years desperately searching for the baby boy she gave up as a teen mom. She left messages all over social media, hoping to find him.

"'If you were born on this day in LA at this time please contact me,' and he did one day," she said.

Now Bridges is desperate to find his killer.

"I really would like some answers to know somebody is out there living their life driving around happy while my son was killed and left on side of the road is unbearable," she said.

John Morrison was 35-years-old when he was killed in the early morning hours of August 18, 2014. It was a hit and run; his body was found in the median of Highway 321 just outside of Hickory near Highway 127.

"He wasn’t found until the next day. He laid on the road. We don’t know if he was dead or alive laying on the side of the road," Bridges said.

Morrison suffered from seizures and couldn’t drive, so he walked everywhere.

"It was his girlfriend's birthday, and she worked the night shift, and he had baked her a carrot cake that day, and he wanted to take her a cake after she got off work," Bridges said.

Investigators said whoever hit Morrison caused the traumatic brain injury that killed him, and, incredibly, there was not a single piece of evidence left behind.

Highway Patrol Trooper Kenny Evans has been on the case since the beginning.

"The vehicle that struck Mr. Morrison left no debris behind, so it’s unidentified," he said.

"It’s very frustrating being the primary investigator for five years. It's very frustrating. We want to find out what happened that morning," he added.

No one wants to find out more than Bridges who said Morrison started calling her "Mom" not long after they reconnected five years ago.

"He was just like he was never gone. He went from my arms in the hospital to 30 years later being in my arms. That first hug was amazing. The last hug was amazing, too. I didn't know it would be the last hug," she said.

It's a pain Bridges said never goes away.

"I lost him twice. The last one is the worst. I know I won’t run into him somewhere," she said.

If you have any information that could help solve Morrison's case, call Highway Patrol at 828-446-5500. You can also leave a tip on Facebook.

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