Transcript for Texas woman discovers a shocking truth about her conception: Part 4
We go to Colorado every summer. With my husband working so much, it's really the only time that we have together where we can just be a family. But this was now the summer of 2018, and during this vacation, eve is spending an unusual amount of time indoors on her computer. She's analyzing her new DNA matches, and corresponding with one of them, a biological first cousin. She was like, "I have family in Texas, the mcmorrises and the Mcmorries." And I was like, "Oh, my mom's gynecologist was a Mcmorries," and we just kind of laughed. We were like, "Oh, small world, ha, ha, ha." And then eve matches with another biological first cousin on 23andme and starts asking him about his family. And he said, "I have one uncle. He lives in nacogdoches, Texas, and his name is Kim Mcmorries." And I asked him again, "Who? Who are you talking about?" And I said, "Oh, , that is my mom's fertility doctor." I think at that point it was -- I was just in shock. I was in shock. So at what point did you sit back and say, "Oh, my god, my biological father is my mom's fertility doctor?" Honestly, it was the moment that that first cousin said his name. It just made sense at that point. This is where "20/20" comes in. A friend of eve's contacted ABC news about this incredible story, and one of the first things we wanted to drill down on was, are eve's conclusions accurate? So we brought in genetic genealogist and ABC news consultant cece Moore, who has a long history with "20/20." And the DNA detective who finally broke the case! In eve's case she was lucky. A lot of cousins and distant cousins of Dr. Mcmorries had taken DNA tests. And so we had a lot of people that we were able to compare against. I built out the doctor's family tree out to his great-great-great grandparents. Because I wanna see is eve carrying the DNA of her mother's doctor's ancestors, and there were plenty of them. There were dozens and dozens of DNA matches, both near and more distant that connected to his ancestors. So in eve's case I could see that she was carrying DNA from all of the recent ancestral lines of Dr. Mcmorries' family, meaning all of his great-grandparents, all of his grandparents. And so that gives me a lot of confidence that we've identified the correct biological father. You reached the correct conclusion. Part of me kind of wanted it to be wrong. It's like bad science fiction. This kind of situation seems to be the stuff of lifetime movies and B Hollywood plots. It's alleged that Dr. Jacobson may also have used his own sperm. Some of them really deal with the novelty of it. Aww, look at you, David. I remember the day you were conceived. With the Saturday night live skit, you get at the ridiculousness of this, and almost, like, the preposterous nature. How dare a doctor do this? Aww, well you're the best kids a fertility doctor could ever trick his patients into having! Dr. Donald cline is the alleged fertility frankenstin. When I stared working on this case we had 23, doctor-conceived children, and now we're up to 55. I've seen well over a dozen of these cases. Cases like this are cropping up all over the country at this a lot of people have compared the fertility industry to the wild west. There's very, very little criminal activity towards holding these people accountable and the question is, are these physicians playing god? It's going to be more likely that this sort of god complex is going to be more concentrated in specific areas, like fertility medicine. Because they are actually able to give life to somebody else. What was it like to tell your mom? Having to tell Steve and having to tell my mom, those were the two most difficult conversations I have ever had in my life. I was just in shock. I was shaking. I couldn't believe it. I really trusted him. Now when you see that photo of Kim Mcmorries holding you at birth, what are you thinking? It looks like he's holding me like a prize. You can see him smiling through his mask with his eyes, and he's holding me up. Like he knows something nobody else knows? It's his little secret. So at this point, Margo and eve are still holding out hope that this might all be some big mistake. Maybe it was somehow one big mix-up or maybe even an accident. Dr. Mcmorries is the only person who has the truth and the answers. So eve realizes she has to confront the doctor and decides to write him a letter. Dr. Kim Mcmorries. Through genetic testing, I recently learned that I am not biologically related to donor 106. Through publically available genetic testing data I am biologically related to certain relatives of yours. My hands are shaking. Hi, I need to send this certified mail. All right. It's done. My heart's about to jump out of my chest. What will Dr. Mcmorries' explanation possibly be? Eve is about to find out.
This transcript has been automatically generated and may not be 100% accurate.