"I didn't get to see her grow up, I didn't get to see her have a boyfriend, get married, have children. You know, things you want for your children," said Candy Clayton, Cortney's mother.
Cortney was abducted in September of 1988 when she walked to a convenience store down the street from her house in Stamford.
"My son, he went up to the grocery store to get himself something to drink and bring her home. He comes back and says, 'Dad, she's not there,'" recalled Stan Clayton, Cortney's father.
The Claytons immediately called police. The FBI, Texas Rangers, and local authorities searched for Cortney for months.
"Until she was found, there was always the fear that you wondered what was happening. Was she being hurt, was she being fed, was she already dead," Candy said.
Some of those questions were answered in March of 1989, when a hunter found Cortney's remains 50 miles away in Moran. The answers to so many other questions remain a mystery, including who killed Cortney.
"We have no idea if it was a man, if it was a woman. So there's that part that's not final," Candy said.
The Claytons own a monogramming business in Stamford. When Colorado City teen Hailey Dunn went missing, they did all of the monogramming for the Hope for Hailey shirts for free.
"We just wanted to do our part. And that's what we did," Stan said.
Authorities have told the Claytons the only hope of knowing who murdered their daughter is if they tell someone else or turn themselves in.
"There will probably never be an answer," Stan said.
Cortney's case has been turned over to the Texas Rangers cold case division.