A DNA kit a family decided to test out for "fun" has revealed a devastating 12-year-old mix-up.
In 2007, Vanner and Donna Johnson, from the US state of Utah, started their journey with IVF and eventually the couple welcomed their second child.
More than a decade later, the couple decided to do a 23andMe DNA test, thinking it would be fun, however they were shocked when they received the results about a month later.
The results for their second child showed Ms Johnson was the mother, but the father was "unknown", meaning Ms Johnson's egg was fertilised with someone else’s sperm during the IVF process.
“When my results showed up showing two sons immediately and seeing our oldest was a half-sibling to his younger brother, through me, we knew there must’ve been something wrong,” Ms Johnson told ABC4.
The couple's second child is now 12-years-old and they waited a year to tell him his father was not his biological parent.
“There were a lot of emotions we had to work through including separating the love of our son which has not changed…to the issue that we were dealing with," Mr Johnson said.
The Johnsons started trying to track down their son's biological father, eventually determining it to be a man named Devin McNeil.
Mr Johnson found Mr McNeil's phone number and was eventually able to get hold of him, and the two agreed to speak later over FaceTime.
"We weren’t very credulous at first but the more details that came out the more evident it was that there was something that had happened that involved us," Mr McNeil told ABC4. He and his wife, Kelly, went through in vitro years ago.
Families file lawsuit against fertility clinic
The two families eventually worked out their paths crossed at the University of Utah Center for Reproductive Medicine about 14 years ago, potentially when the mix-up happened.
Despite the McNeils living in Colorado and the Johnsons living in Utah, the two families have supported one another and have even met in person.
While they go about their lives, both the Johnsons and the McNeils have decided to file seperate lawsuits against the University of Utah Center for Reproductive Medicine.
The university provided a statement to ABC4 and said they cannot provide comment on patients without consent, though care and safety of patients was their main goal.
"If patients come to us with questions or concerns about their care, we evaluate our care and procedures and, if necessary, make changes to prevent harm from happening to other patients," the statement said.
"Our providers and staff strive to provide excellent care and we constantly work to make improvements.”
The families are urging for changes to be made to ensure something like this doesn't happen again and both encourage anyone who has undergone IVF to take a DNA test.
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