We continue with more of "20/20." Once again, David Muir. Reporter: Bridget has now reached her final hurdle, her own father. Last time, she couldn't even look at him. Can you follow my hand over to... See More
We continue with more of "20/20." Once again, David Muir. Reporter: Bridget has now reached her final hurdle, her own father. Last time, she couldn't even look at him. Can you follow my hand over to your dad? Good, good. Stay focused on the hand. Reporter: On this day, she gets closer, much closer. Touching Dr. Weg's hand. And he is touching her father. Catch your breath, stay focused. Go ahead. Reporter: And then, Bridget touches her father herself, the first time in six months. Not good. It's hard. Reporter: These are her last steps before Bridget decides she can finally try to go home. The next session and Bridget sits between her parents on the couch. She's about to move toward her father. Hey, daddy. Reporter: And finally, an embrace. Hey, buddy. Hey, daddy. Reporter: This was undoubtedly her biggest breakthrough yet as she tries to get home. While for chelle, the biggest challenge is that trip away from home, that eighth grade prom, an overnight trip with some of those same students she once feared. Hi. Reporter: How is it going? Getting ready for the prom? Good, yep. Reporter: So this is the fancy dress. Wow, that's pretty. Yeah. Reporter: She's proud of her dress, proud of being here. And her friends, they're proud of Michelle. She has kept her OCD a secret until now. She told me that she had, like, a disease where she was kind of afraid of what might happen to her if she, like, came into contact with other people. Reporter: But as her friends get ready in that room, they have no idea on the inside, Michelle is still fighting that OCD. You don't do school activities. Nope. So this is a big deal. You know, sleeping in a bed that's not mine, not being with family, you know? So, I mean, it's different. Reporter: A lot of people might think, well, that's just being a little homesick, that everybody gets that. Yeah. But I think for me, because I've been with family for just four months straight, it's harder for me to let go. Reporter: And you're feeling it already? Do you feel badly because you've left them? I guess. But I know it's what my mom and my dad want me to do. Reporter: So you're doing this in part for them. You can't mess up your make-up. As the girls assemble in the hallway, getting ready for the ballroom, Michelle shares the anxiety that is creeping back. I mean, I'm so worried that OCD is going to pick on something. And then I'm going to have to obsess over it. Reporter: She has already quietly tested the bed by sitting on it just to prove to herself that a bed where strangers have slept won't make her dirty, just like she tested that gym locker long before and that walk through the Kohl's parking lot. But this time, she was testing herself without her mom, without her coach. You did it on your own as your friends were in the room. Mm-hmm. Reporter: Do you think they even knew that you were trying -- No, probably not. Reporter: Her friends are waiting. That prom is about to start. And just outside, just out of sight, mom waits as well, just in case. I don't want anybody to see me because I don't want her to feel bad, but I need to be close enough that if she does have a panic attack or if she can't do it, that I can be able to be there.
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