GRAVES COUNTY, Ky. — With every piece of tape, with every missing person poster comes new frustration.

"Someone had to have seen her," Greg Williamson says of his daughter Sidney.

The Graves County High School freshman disappeared Tuesday. No one has seen or heard from her since.

For the past two days, the smiling face on the missing posters is all too much for mother Stefanie Williamson.

"You're not supposed to see your child like that," she said, tears cascading down her cheeks. "They're supposed to be at home with you."

But she is not. Investigators said she never boarded the bus Tuesday afternoon. Sheriff's Deputies believe Sidney left on her own free will. But now, they are bracing for the worst.

Sidney Williamson went to school Tuesday with a duffel bag and a plan to meet up after class with someone she became acquainted with on Facebook. It was someone she described to friends only as "a guy from Florida". That guy, deputies believe, is over 18.

Williamson was captured briefly on a school security camera heading away from school property.

"Her phone hasn't been turned on since," Sheriff Dewayne Redmon said.

But he has waited for her to text a friend, to get on Facebook. He has heard nothing.

"In this particular case, she's just disappeared."

It is a heartbreaking reality for the parents who have spent the past two days looking at the picture on the missing posters, praying to see her smile once again.

"We love you, Sidney, and we want you to come home," Greg Williamson said.

Deputies are in the process of getting search warrants for Sidney Williamson's cell phone records and Facebook account. Additionally, they are combing through video surveillance from area stores.

Williamson is described as 5 feet 4 inches and weighing about 115 pounds. She has brown hair, hazel eyes and wears braces and glasses.

Anyone with information is asked to call the Graves County Sheriff's Office at (270) 247-4501.