BUTLER COUNTY — As attention is focused on the search for a missing Fairfield woman, a mother in Hamilton hasn’t given up hope of finding her son.

Weeks have now gone by without word of Katelyn Markham’s whereabouts. She was reported missing on Aug. 14. But months have passed since anyone has seen Billy DiSilvestro, who went missing on the night of the Super Bowl, Feb. 7.

The two are among 163 open cases of missing adults in Ohio, according to the National Missing and Unidentified Persons System.

As time goes by, the chances of finding out what happened to them decline, as statistics show less than 25 percent of missing persons cases are ever solved, according to NamUs.

Not knowing where a loved one is or what has happened to them is a sickening, heart-wrenching experience, said Debbie Estes, DiSilvestro’s mother.

“I’m feeling the worst the longer it goes on, but you can’t grieve for something you don’t know,” Estes said.

“I try not to sit and dwell on it because it usually makes me half sick. I wouldn’t wish this on anybody. It’s the most horrible feeling.”

DiSilvestro was last seen in the city at a Ross Avenue residence on Super Bowl Sunday, Feb. 7.

Estes said she believes her son went to the friend’s home to drink alcohol and watch the game.

He called his mother’s and grandmother’s from his cellphone around 2:30 a.m., probably to get a ride home, Estes said. When no one answered, Estes said she believes her son left the apartment and started walking to his grandmothers home about two miles away on Stahlheber Road, which would take him through Milikin Woods.

Though he was last seen in the city of Hamilton and there is the potential that he was a victim of a violent crime, Hamilton police are not investigating DiSilvestro’s disappearance. That’s because DiSilvestro was reported missing from his grandmother’s house in Hanover Twp., which falls under the jurisdiction of the Butler County Sheriff’s Office.

Authorities there have devoted a lot of man hours and resources trying to solve the case, but promising leads have dwindled, said Lt. Mike Craft, detectives supervisor at the sheriff’s office.

“I know (the Markham case) is in the media spotlight right now, but Billy certainly hasn’t been forgotten in this department,” Craft said. “We have done extensive work and investigation in this case.”

Craft said investigators have conducted search warrants, subjected witnesses and persons of interest to polygraph tests and have pursued every lead, from a possible homicide to medical emergency. While some leads have been discredited, Craft said investigators are “not ruling anything out.”

“This department has spent hundreds of hours on this case,” he said. “There have been no new leads in a couple weeks. We’re still looking for information.”

Estes posts flyers every day all around the city, only to have them quickly removed by city officials who are enforcing city codes. She has created Facebook pages to encourage the flow of information and has made sure her son’s case is in every missing persons database she can find. Her car is like a billboard advertising her son’s missing poster.

Estes felt more hopeful than she has in a while on Saturday, when the Texas-based search and recovery nonprofit organization EquuSearch led a massive search effort for Markham in wooded areas around Fairfield. The nonprofit’s founder, Tim Miller, agreed to help a smaller-scale search for clues in the DiSilvestro case, with a few volunteers offering to walk the same path DiSilvestro may have walked on his way to Stahlheber. Both efforts ended in frustration, but Estes said she is grateful for the renewed attention in her son’s disappearance.

“The thought of someone hurting him, that’s what bothers me,” she said. “If I don’t get out there and do something, I feel like I’m not doing enough for him.”

Contact this reporter at (513) 696-4542 or rwilson@coxohio.com.