In 1998, family members were told Bobby and Myoung Whitt had returned to her family in South Korea. (WCPO.com)

A member of the lawn crew spotted it in the brush tangling beneath a billboard, something glinting in the North Carolina sun.

It was Sept. 25, 1998, in Mebane, N.C. Highway traffic ripped along on nearby Interstate 85/40, the major thoroughfare stringing together Raleigh, Durham and Charlotte. The sun-bleached small human skull was just outside of the wood line.

“Had it been just a few feet further back, you wouldn’t have even seen it,” Maj. Tim Horne, an investigator with the Orange County Sheriff’s Office and one of the first law enforcement members on the scene, recalled recently to ABC 11. “The child’s legs were still draped over some brush and it was partially clothed.”

Although the body was badly decomposed, investigators soon learned the child had been killed by strangulation. Identifying the victim, however, turned out to be difficult. As the Orange County Sheriff’s Office recounted Tuesday in a news release, the body did not fit the description of any missing children locally or in a national database. Media attention on the boy failed to kick loose any leads. The case went cold. The child became known as the “Boy Under the Billboard.”

But as the years piled up, Horne, the sheriff’s investigator, developed an ingenious way to keep the unsolved case from being buried under new police work.

“I always kept the case file box under my desk, where it was purposefully in my way,” Horne said in a statement from the sheriff’s office. “Every time I turned, I hit it with my leg. I did this so the little boy couldn’t be forgotten.”

After more than two decades, investigators finally got a break in the case this week thanks to new genealogical DNA testing, the same technique that has led to a raft of cold-case arrests in the last year, including the prosecution of Joseph James DeAngelo, the accused Golden State Killer.

But when the boy’s body was finally identified in December, it only complicated the case for Horne. Instead of dealing with a single murder, the investigator realized he was now facing two unexplained deaths.

During the years Horne and other investigators worked to fit a name to the body, Natalie Mosteller was scouring the Internet for a lost family member.

Growing up east of Cincinnati in Sardinia, Ohio, Mosteller had been close with her cousin, Robert “Bobby” Adam Whitt. Born in Michigan in January 1988, Bobby was the son of her uncle, a Caucasian male, and his wife, a Korean woman named Myoung Hwa Cho, according to Cincinnati’s WCPO.

“I’m the oldest of three girls, and he was my only first cousin,” Mosteller recently told the Raleigh News & Observer. “He spent a lot of time at our house, and he was the little brother that I always wanted and never had.”

Mosteller recalled Bobby as a sweet boy who loved playing video games and air hockey. “He had an air hockey table in his bedroom,” she told ABC 11.

Mosteller’s mother, Barbara Moellmann, also fondly recalled both the boy and his mom.

“Bobby was a very brilliant little boy,” she told WCPO. “And he was funny. He had a real dry sense of humor . . . [Myoung] was funny and fun. Literally, I’m going to have to say, probably the hardest working person that I’ve ever known in my life.”

But when Mosteller was 19 and Bobby was 10, the boy and his family moved to North Carolina. Not long after, the father told his family back in Ohio that he and his wife had split, and that she had taken Bobby back to her native South Korea, Mosteller said.

As an adult, Mosteller tried finding traces of her long-lost cousin online.

“I personally, my sisters as well, spent a great deal of time trying to track him down on Facebook and Instagram, things like that, with no success,” she told WRAL. “We were hoping, like worst case scenario, that his family in South Korea had turned him against us somehow and that’s why he wasn’t trying to reach out to us.”

Back in North Carolina, after decades of banging his leg against the case files for the “Boy Under the Billboard,” Horne finally had a breakthrough in late 2018. Throughout the year, cold cases had been solved using genealogical DNA, a technique that involves comparing forensic data from crime scenes and unidentified victims into public ancestry databases.

According to the sheriff’s office, Barbara Rae-Venter, a genetic genealogy consultant who assisted on the Golden State Killer case, analyzed the mystery boy’s genetic material and determined he was the first-generation son of Caucasian and Asian parents. Sifting through information on the public database, Rae-Venter was able to track down a relative from Mosteller’s extended family.

On Dec. 26, the unidentified family member returned a call to Horne. The relative recounted Bobby’s disappearance, and explained no one had reported the child missing because the family believed he had gone back to South Korea with his mother.

Further DNA testing confirmed the remains found in 1998 was Bobby, the News & Observer reported.

But the revelation only led to another open question: If the boy was Bobby Whitt, where was his mother?

Horne began combing local databases for reports of an unidentified woman matching Bobby’s mother description.

On May 13, 1998 — four months before Bobby was discovered — an unidentified Asian woman’s body had been found behind a debris pile in Spartanburg County, S.C. According to information released by local authorities, the woman had died due to “respiratory insufficiency.” The body had ligature marks from where she had been bound.

Like Bobby, the woman had been discovered on a road running parallel to Interstate 85, more than 200 miles from where the boy was dumped. According to the Associated Press, further DNA testing matched the woman as Bobby’s mother. South Korean authorities helped investigators determined the woman was Myoung Hwa Cho.

Bobby’s father and Myoung’s husband has yet to be publicly identified by authorities. However, according to federal court records, he pleaded guilty in 1999 to federal charges in North Carolina related to an armed robbery and is serving a prison sentence. He is not eligible for parole until 2037.

Sheriff officials told the News & Observer that Bobby’s father confessed to both murders last week. The Orange County Sheriff’s Office said he will not be publicly named until prosecutors decide whether he will be charged with the two murders, as investigators are not sure where the actual killings took place.

His family members were shocked by the revelation, according to WCPO.

“Not in a million years would I have ever imagined that my brother would be capable of doing this disgusting, vile, heinous act,” Moellmann, the sister of Bobby’s father, told the station. “Not in a million years would I have imagined him to be a monster hidden in plain sight.”

For Horne, the investigator who was one of the first officers on the scene in 1998, resolving the case was a bittersweet capstone to a career. He retired on Feb. 1, the News & Observer reported.

“We were disappointed and we were disheartened at various stages when we didn’t get the results we were hoping for,” he told the paper. “But we kept batting it around and we never let it hit the ground, and ultimately, we caught this one.”

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