A woman recently found that she is related to her husband by blood.
Marcella Hill broke the news to fans on TikTok and it left viewers stunned.
The bizarre event all started while she was pregnant and researching baby names for her new arrival.
"We were sitting on a couch and I was looking for names for the baby that we were about to have and I was on Family Search," the now mum-of-four said.
"Oh look grandpa's name, grandma's name, great grandma's name, great-great grandma's name.
"Husband is next to me on his own Family Search and he's like 'oh that's funny, we have the same grandpa and grandma's names'."
Marcella thought her husband was joking and had logged into her account by mistake.
But when she had a second look to read the names, she made the shocking realisation.
She continued: "We realised my grandpa is his grandma's first cousin.
"So he calls his grandma and I call my grandpa and we asked them if they know each other.
"They live together when they were growing up as children - [that means] we are third cousins!
"So when I go to my family union he gets to go to his too at the same time!"
Her story left many viewers baffled and they had questions.
"How did you not know at the wedding?" viewers asked.
Marcella clarified they didn't have a wedding ceremony.
"We got married at a courthouse after work on a Wednesday," she said and showed their wedding pictures.
"This is the picture of us on the wedding day - there we are with the copy machine and the binders in the office.
"And this one we are against the brick wall in a hall way in the courthouse.
"But still, let's say we had the wedding and my grandpa and his grandma were there and we found out we are third cousins at the wedding, what were we supposed to do?"
One viewer said: "Third cousins is not too closely related, it would be different to me if you all had grown up with each other."