"There's not one part of this story that is not truly unbelievable," said Melissa Fox.
Two weeks ago, the Foxes finally got the call they've been waiting years for. There was an arrest in the murder of their 3-year-old daughter, Riley.
"Just to hear those words? , 'We caught your baby's killer.' It was - pretty emotional," said Kevin Fox.
Kevin spent almost eight months in jail when he was charged with Riley's murder. DNA tests proved he couldn't have done it. ABC's David Muir sat down with the couple.
"The big question is: Were investigators so zeroed in that it was Kevin Fox that they missed other clues? Now we learn that a suspect in a burglary right across the street on the same night the Fox's daughter disappeared is the suspect, who was about a mile from the Fox's home," said Muir.
Scott Eby is already serving time for another crime. The Foxes find comfort in the fact he's behind bars, but not in the personal trial they've endured. They believe the initial investigators were consumed with the notion that Kevin Fox killed his own daughter.
"He was in a room for 14 hours straight... He thought the only way out of this room is to agree with the story they're presenting me with and that's what he did," said Muir.
"I know that they did what they did to Kevin on purpose. And so I hate them for that because it wasn't a mistake. It was on purpose," said Melissa Fox.
Watch the full report on 20/20 at 9 p.m.