But Lisa's parents say that isn't true. In the interview with Today Show's Matt Lauer, Jeremy Irwin admitted he "reached (his) boiling point" during questioning Thursday and told investigators he did not want to continue, but says he remains willing to do anything necessary to find his daughter.
"We're still cooperating," he said. "We're still talking to police."
Deborah admitted to taking a lie detector test and says police told her she failed.
"But I don't know how that is possible," she said. "What do you say when someone tells you that and you know you didn't do anything."
Jeremy Irwin says he has not been asked to take a polygraph test, but would be willing to do so. "If that's what it takes, that's what we can do."
Both parents insisted they had nothing to do with their daughter's disappearance and said they had no suspicious of each other.
"He's a good father. He's good to me. He loves her," Deborah Bradley said. "Everybody loves her. No, there's no way. We don't know, which is why we need everyone to continue to look for her."
Click the media player above to see video - used with permission from NBC News - of more comments made Friday morning by Lisa Irwin's parents. For the Today Show interview, watch the video below.