"You just can't even imagine what's going through a young girl's head at this point at time," Smart told ABC affiliate WKRN in Nashville. "Regardless of what Elizabeth Thomas's situation might have started out to be it could be very different at this point."
The exact circumstances of 15-year-old Thomas' disappearance and her relationship with 50-year-old Cummins are still murky, but Smart says a common denominator is the manipulation of these teens by these older men.
"In our Elizabeth's case they got her to this mindset where she believed that if she did anything they didn't want her to do that they would come and kill her family," Smart said. "Manipulation is what controls them."
Smart says the return of Thomas will depend on the media's coverage of her disappearance.
"I just don't think you can hope to find your child without the media and the coverage because without them you cannot engage the public and get them to help you find her," he said. "It's going to come down to the public seeing something, seeing her or seeing him."