Transcript for Woman on quest to find sperm donor father finds shocking truth about her conception
My name's eve Wiley. I live in Dallas, Texas, and when I tell people my story, their jaws hit the floor. Reporter: It's a story not even we could believe at first. Full of twists and turns, raw emotion. This sucks. Reporter: A secret reveal that would leave eve Wiley wondering who am I and where did I come from? I feel like my heart is just going to jump out of my chest. Five, four, three, two, one. Reporter: Eve's story began 33 years ago in center, Texas, a happy, full-of-life little girl. Who always knew there was something just a little different about her. Dad Doug passed away when eve was just 7. And at 16, while snooping through her mom's e-mails, eve uncovered a bombshell. I saw all of these e-mails about artificial insemination and after about the 10th or 11th one I clicked on it. And when I clicked on that one I scrolled down. And it said I'm gathering information for my daughter, she was born in 1987. And it was my birthday. Reporter: What was your reaction? What the ? I wasn't angry. It was one of those things where everything kind of made sense at that point. My sister and I look absolutely nothing alike. I'd been married for about a year, and had not had any success, so I decided that I'd seek out medical attention, help. The doctor was very well-known in the area. He is an obgyn, and he does work in fertility issues. He was that doctor in the community that everybody respected and really thought very highly of him and absolutely trusted him. Reporter: After some failed attempts at artificial insemination, Margo chose an anonymous donor, she knew him as donor 106. He was interested in politics and film. And that's so alien to me, I thought, he's the one. Reporter: So at what point did you decide I want to find him? Immediately. Reporter: And when eve turned 18 she sought out donor 106 and found him. The first phone call was tracking me down to make sure I was Steve Shull to make sure I was the donor. Two weeks later they reach out and say one of your genetic offspring wants to reach out to you. Reporter: A self-proclaimed hippy, Steve had traveled the world before settling in just scraping by, he found an ad by a local sperm bank. He and eve set up a face-to-face meeting It felt kind of natural. It felt like we truly genetically connected. There was no doubt in my mind that this was my daughter. Reporter: It was perfect. The families blended, and eve was on top of the world. The poster child for the ultimate donor-conceived success story. Briefly. Until we found out otherwise. Reporter: Wanting to know more about her new family history, eve turned to commercial DNA testing. My name is Megan, and I met my birth mom for the first time today. Then I started thinking, hey, I could do this and maybe find some siblings. I got the kit, spit in the tube and sent it off and waited. Reporter: The problem was, the matches each was getting led back to geographic areas where Steve, donor 106, had no family connections. She came to me and said, mother, there's something wrong with the things I'm seeing. These people that are popping up in my DNA. Reporter: And when eve got on the phone with one newly-discovered relative, everything changed. He told her he had an uncle, Dr. Kim mcmoreys. She remembered the name. It was her mom's fertility doctor. 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. I was just in shock. I couldn't believe it. I really trusted him. Reporter: Rocked by the revelation about her conception, eve demands to know why, writing to Dr. Mcmoreys for answers. Through genetic testing I recently learned that I am not biologically related to donor 106. Through publicly available testing data I a am biologyki related to certain relatives of yours. Okay, looks like nothing today. Reporter: But finally. Feel like my heart is, whoa, going to jump out of my chest. Okay. Five, four, three, two, one. Good afternoon. All right. I have a certified letter for you today. Okay. There it is. All right, great, James, thank you so much. All right. Dear Mrs. Wiley, I have searched through our medical records. Trying to find some answers to your questions. Reporter: The doctor writes that when eve's mom was going through treatments they weren't having success. In fact he says donor 106's sperm failed. He discussed adding a local sperm donor to the mix. I told him I didn't want a local donor. We talked about the problem that number 106 wasn't working. I told her about the option of using number 106 as primary but augmenting it with another sample. I thought she understood this. Reporter: Margo insists that conversation never took place. Absolutely not. That just didn't happen. Reporter: But one thing becomes crystal clear. Dr. Mcmoreys admits he never discussed with Margo that the other local donor sample he mixed with donor 106 was his own. The sample came from an old donation from his medical school days. My characteristics were closest to the characteristics of 106. Reporter: This leading expert told us this is highly unethical, today or 33 years ago. If the doctor wanted to be the genetic parent of a patient's offspring, he would have to engage in a very deep and thorough conversation in which the patient gave informed consent. Reporter: Dr. Mcmoreys declined our request for an interview, but through his attorney told us he had a good reason for not telling Margo he was using his own sperm. He says donor anonymous agreements prevent it. He is a respected obgyn and respected for trying to help his patient as much as he possibly can. Today eve is determined to write the final chapter of her story. She lobbying to make it a felony for any doctor to use any donor's sperm without the express consent. We found out that this was not a crime. This man was my mother's doctor. He was not her donor. Sorry about your experience, but through your testimony in the future we'll be able to hold people accountable. Reporter: She still considers Steve her dad, and she also knows her story may have more twists to come. Do you sit back at any moment and think wow, I've got a beautiful life? I've got an amazing husband, I have two amazing kids. I do, and I'm happy I'm alive, but it doesn't make it right. It doesn't make it okay. My pain is still my pain. Reporter: For "Nightline," Kyra Phillips in Dallas, Texas.
This transcript has been automatically generated and may not be 100% accurate.