Sumter, SC (WLTX) - It's been five weeks since 80-year-old Barbara Nave went missing from her Sumter home on Tondaleia Drive.

Authorities say they've exhausted numerous leads to find her.

"It just doesn't make any sense,” says Paul Nave, who last saw his mother on February 4th.

Paul lives in Savannah, GA and has been commuting back and forth to Sumter for the case. He says his mother has her right mind and has been teaching English to employees at Continental.

"Up until her disappearance, she got to live and do what she wanted to do,” says Nave.

He says every day that she’s been missing he has gone to sleep wondering where his mother may be.

"And I wake up every morning wondering what's going on,” says Paul. “It's just not something that I every anticipated that I would have to deal with as most families probably don't. This is the first time I've had to go through this, so I'm just kind of making it up as best I can along the way."

The Sumter County Sheriff's Department is treating this as a missing person's case.

"We've used pretty much everything we have to try to find her,” says Ken Bell.

Bell, public information officer for the department, says they have searched Nave's entire 20-acre property and outlying woods, but haven't found anything that can lead to her whereabouts.

"It's really puzzling, because there's no clue about why she left, except she left her dogs in the house, her purse, a little bit of money and the keys, all her personal belongings were in the home,” says Bell. “So, that told us that she left thinking she would be right back probably."

The department is now asking for the State Law Enforcement Division to help in the case.

Paul says he has faith that law enforcement will help bring his mother home.

"The odds of me finding my mother on my own is pretty much zero. So, I'm relying on people that have that kind of experience to help me out, especially since they are boots on the ground and I'm almost three hours away."

Sumter deputies say they're continuing to listen to tips from the public.

If you know where Barbara Nave can be found, call Crime Stoppers at 1-888-CRIME-SC.