Reporter: The pretty house with the wraparound porch in oregon is now in the catt's rear view mirror. Tonight they're in the big house, behind the bars of the fort bend county jail in texas. The...
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Reporter: The pretty house with the wraparound porch in oregon is now in the catt's rear view mirror. Tonight they're in the big house, behind the bars of the fort bend county jail in texas. The family has been held in separate cell blocks. They haven't seen each other in over a year as they await their day in court. Jailhouse life has taken its toll. Scott says there's not enough food and he's lost more than 70 pounds. Almost unrecognizable to his own mother when we showed her footage from our interview. He's a grown man. He doesn't look the same. Oh, I miss him. He's old. I don't wanna see anymore. Reporter: She's heartbroken by what her son did to the grandchildren she'd help care for after their mother died. It's so hard, I wish I knew why he did this. I will never know. Reporter: When we sat down with scott he wanted us to believe he was a changed man a father who would do anything for his kids. If you were offered a deal where you had to spend 25, 30, 40 years in prison in exchange for both of your kids going free, would you take it? For them goin' free? Absolutely. What about life in prison? Sure. Scott catt is a manipulator. He is a terrible excuse for a father. No one would be here today, except for the fact that scott catt decided a life of crime was easier than actually going to work every day, and raising his children. Would you have said you're a good father? I thought I was. Do you think you are now? I have serious doubts. I mean I think that we're all sittin' in here right now because of my inability to be a parent. Reporter: What would beth say, your first wife? What would she say about you dragging your kids into -- I can't even imagine. Can't even imagine. I'm just -- I'm really ashamed. My mommy that's when he cries. Reporter: He didn't cry about his kids but about his wife. Yes. Reporter: Abby's lawyer gave us letters from her dad for them doing hard time so he could do less. We went back last week to confront scott face to face. This is your letter to abby. Where did you get this? Reporter: It's -- it's your handwriting, isn't it? Yeah, definitely is. Reporter: And it's your letter. Yes. Reporter: You told me recently that you would be willing to spend life in prison in order that your kids do not. I would. Reporter: But here you are asking her essentially to do time for you. Look, I -- yeah, I was tryin' to manipulate. I'm tryin' to get something they could live with. Reporter: Everybody? You got your kids involved in this, and you're asking them to do time for you. It says it right here. Here it is again, "i do believe that you doing prison time will be good for me. And I know that wasn't an easy choice for you." And that's what she said to me in the previous letter, that she was willin' to do that. Reporter: Wouldn't most parents, say, try to dissuade their children? Say, "please, don't admit to anything. I will take the entire blame here." I would love to, but they have so much evidence on everybody that what are we supposed to do? Reporter: What's interesting is that you can't even leave 'em alone. It seems that you caused so much havoc in their life beforehand that you're even trying to -- you're even trying to manipulate them from behind bars, and us. What do you want me to say to that? Reporter: In another letter scott encourages abby and hayden to exaggerate his addiction in their interviews with us all so that his story would appear more sympathetic. Tell them I led a dual life involving drugs, alcohol and women and we can with them a little. Reporter: You clearly told your. You know. Reporter: Kids to manipulate us. I wanted to get some sort of, wow, some sort of movement on my case, something. It was a joke. I was joking around. That's the "ha-ha" part. Reporter: I don't understand the humor. Well, that's the humor of somebody that's done a lotta drugs and alcohol. Reporter: He has done research on what would make them have a better story. So being a dug addict. Being an alcoholic, your audience would excuse it and feel sorry for him. I did everything wrong. I wish I could take it back. I can't. There are so many regrets. Reporter: Your father says he blames himself. He says he lied to you for many years. Do you believe him now? Am I supposed to believe him all of a sudden? I want to. I always wanted to. I believe he feels remorse. But I also believe that he still didn't have my best interests through all of this, through all of the court stuff. Reporter: When we told scott his kids thought he failed as a father. He was dumbfounded. Did they forget the happy times? They don't remember the trip to disneyland? I wish I could have made those memories a little more lasting for them. Reporter: And unbelievably despite everything, abby and hayden say, they forgive their father. I've forgiven him because i have to for myself. And so I can start to live a normal life. I don't want hate, anger, and any of that in my heart. Reporter: If your father were right here, hayden, what would you say to him? Uh, you know, I'd tell him that I forgive him and that i don't want him to carry this burden around with him for the
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