Eve Wiley has spent the last 14 years building a relationship with the man she thought was her biological father.
Since the US woman was reunited with Steve Scholl, the man she believed was her donor, the pair have become extremely close, Kidspot reports.
"I call him dad," the 31-year-old told Morning News. "We say I love you.
"We spend holidays together and he actually officiated at my wedding."
So Eve and her husband weren't expecting any surprises when they decided to trace their family's health history using genetic testing services 23andMe and Ancestry.com.
She was told the couple used California Cryobank, where they selected Steve Scholl as their sperm donor.
Working with the fertility doctor, who remains anonymous, the couple tried five times with Steve's sperm to fall pregnant.
But on their sixth attempt, no one had any idea the doctor has allegedly mixed his own sperm with Steve's.
Although the doctor believes that the couple had given him permission to mix Steve's sperm with that of an anonymous local donor — Margo denies giving that consent.
According to 20/20, the doctor has since admitted that Margo was never told that it was his sperm used in the insemination.
Now Margo and Eve are left grappling with why the doctor, who actually delivered Eve, allegedly artificially inseminated her mum with his sperm against her will.
"He was that doctor in the community that everybody respected and absolutely trusted him," Margo said in an exclusive clip from their upcoming interview on 20/20.
"He was kind of a hero for my parents," Eve added, fighting back tears
"He gave them the one thing that they wanted — and it was a child.