Transcript for TV star responds to co-star's sexual abuse allegations
hour with that ABC news exclusive. Scott Baio is here live and in just a moment he is going to address those explosive allegations made by his former "Charles in charge" co-star Nicole Eggert but before we talk to him, we want to give you a closer look at the story. This morning, Nicole Eggert and Scott Baio both speaking out about allegations of sexual abuse. Nobody likes to be told what to do. Reporter: Eggert doubling down on her claims her "Charles in charge" co-star molested her while the two worked together on the '80s sitcom telling Megyn Kelly it started when she was 14 and continued quite often through the age of 16. The issue with him is that he was our boss and, you know, he also was telling me, you know, you can't tell anybody. This is illegal. I'll go to jail. The show will be over. Everybody will be sued. You know, you'll be out of a job and, you know, you'll ruin everybody's life and it's scary. That's intimidating especially when you're that young. Reporter: The allegations initially playing out on social media with Eggert tweeting over the weekend, ask Scott Baio what happened in his garage at his house when I was a minor. Creep. I'm going to knock down these false claims against me. Reporter: He's refuting all her allegations in this post presenting past letters from his attorneys denying similar claims and citing Eggert's past interviews as proof there was no misconduct. But Baio did admit to one consensual encounter he says happened after she turned 18. I remember her calling me and asking to come over and coming in my house one time and seducing me. Reporter: But Eggert saying that's not what happened. She says it happened at her house when she was 17 and "Charles in charge" was still in production. Did you initiate it or he. He initiated it. Any doubt in your mind you were under the age of 18. No doubt in my mind. Scott Baio joins us live now. You heard Nicole. She says she has no doubt she was under 18 when the two of you had sex. You say she was 18 and you also say you have proof. I do. I do have proof. "Charles in charge" ended in the fall of 1990 and she said in the NIK Ritchie interview, the dirty.com we had sex when she was 17 and she said we had sex long after "Charles in charge" was done. Nicole Eggert was born in January of 1972. "Charles in charge" ended in the fall of 1990, so that would have made her an adult, 18 plus and she said that it happened long after "Charles in charge" was done. Those are her words. Correct and that was a radio interview with NIK Ritchie you bring up. Now she says it did happen when it was filming. That she lied at the time to protect the show because that's what she thought she needed to do. She lied at the time to -- so I'm trying to figure out which time she's lying and which time she's not lying because the story seems to change quite a bit. So and I can't keep up with her quite honestly. I want to bring up NIK Ritchie. He issued a statement. Had is the man she was talking to and we should point out he and Eggert both share a manager but now says Nicole was distraught after that interview. She told me it was much worse than she described on air. She said he molested me as a child and I didn't know any better. I can vividly remember that statement. It's not one you would forget. What happened with you and Nicole when she was 14, 15, 16? Absolutely nothing. And I find it interesting, Amy, that the moment that her first allegation that we had sex when she was 17 which is not true as soon as that was proven to be 100% false, she comes up with a new story where something happened once a week for years. Now, I don't know if you've ever been on a sitcom set but on any given day on every day and especially "Charles in charge" which was like a picnic every day, one of my favorite jobs I've ever done there's teachers, parents, family, crew, producers, my dad. So how any of this could have happened is absolutely impossible and I find it -- I don't know how anybody can believe what she's saying when her first allegation of having sex when we were 17 had been proven to be 100% false and her story keeps changing. It comes up -- she makes up new things. I about the way, I'm not the first person she's done this to. Okay. She got very specific about you. She says Eggert said you had sexual contact with her touching her inappropriately when she was 14. She says and you mentioned in that it was not a one-time incident that that happened like once a week. How would you describe your relationship with Eggert on the set? Was it strictly professional? No, it was great. Flirtatious. Amy, I can tell you and I mean this sincerely one of the most fun things I've ever done. Talented girl. We had a great time on the set. Everybody liked each other. Everybody got along. Nothing inappropriate? It was impossible because when a child is on a set, they're either in school or they're on the set with a teacher and their parents. Never alone with her. No, unless I was in a scene alone with her and directors and producers and crew guys are watching. Never. Never. It's impossible. And the amount of time that we spent on the show was -- You never saw her off the set? Off the set? I saw her in the studio a lot. Yeah, off the set. She mentioned your garage in one of her tweets. I have no idea what that means. I have no idea. So you can't just keep making up different things. I want to ask you about this. Adam who played Nicole's brother reportedly said he witnessed inappropriate cuddling between you and Nicole on the set and then Adam Karl who is credited with one appearance on the show tweeted he remembers her crying about you. Why do you think they're saying that? Are they lying too? I don't know what they're saying. I have no idea. I don't know why they're saying it. I don't -- there were so many people on that set. Nobody said anything until -- and by the way, Nicole and I were friends after our only sexual encounter where she, she aggressively sought me out because she wanted me to be her first so that she would be good for her boyfriend, those are her words. You say she seduced you. Yes. You stand by that. Absolutely. You weren't attracted to her. You didn't seek her out. Absolutely not. You didn't try to date her. Absolutely not. No. Something else of interest, you also told Eggert to go to police if she had these allegations and she now says she may do just that. Do you have any concerns? No. Why would I have a concern over something that I didn't do? And rather than take your case to social media where people tend to beat up people like me, why not do it through the proper channels instead of making the appearance because you put up allegations like that and it becomes like wildfire. Well, we know that you have certainly spoken up loudly and -- Listen, I have to tell you one more thing, Amy. I mean and people are forgetting this. And it's very important how this is affecting me. Why somebody would come after me, my reputation and stop me from doing something that I love doing that I've been doing since I'm 9 years old and more important than that, is my wife. And I have a 10-year-old daughter. And my 10-year-old daughter does not need to be hearing about this from friends at school these false allegations. Her job is thought to defend me. My job is to defend my daughter her job is to be 10 years old and that's why this has got to stop. Scott Baio, thank you so much. You're welcome. Thank you for having me.
This transcript has been automatically generated and may not be 100% accurate.