Family isn’t always about blood, but it is about loving the people in your life. And sometimes, even when people make major big mistakes, love prevails.

Marinella Alagna and Gisella Fodera from Mazara del Vallo in Siciliy both gave birth to baby girls shortly before midnight on Dec. 31, 1998.

Their babies were born only 15 minutes apart. Somehow in the shuffle, the nurses got the babies switched around and gave the wrong child to the wrong mother.

According to Good News Network, though the mothers noticed the babies they’d been handed weren’t wearing the outfits they’d brought, the nurses said it was fine.

And for three years, it seemed to be. Until Marinella spotted a 3-year-old girl named Caterina at her youngest daughter’s school that bore a striking resemblance to her other two biological daughters.

“I recognized Caterina’s mother, Gisella Fodera, from the maternity ward and got suspicious — 15 days later we did DNA tests and my mind went blank. It was too surreal, too impossible,” Marinella told the Times UK, according to Today UK News.

Around two weeks later, DNA testing proved Alagna’s hunch, and the two families were left in a quandry. They had the “wrong” daughters, but they’d loved and raised the babies as their own.

“I challenge anyone to raise a daughter for three years then give her up over a simple mistake,” Gisella told Today UK News.

So they had a rather unorthodox solution: Both families would live together, allowing them to be with the children they’d raised as well as their biological children.

“The girls effectively grew up with four parents and eight grandparents, and the experiment worked,” Mauro Caporiccio, author of the film “Sisters Forever,” said, according to The Times UK.

“They chose to live together during the weekends and free time. And the girls were classmates until college.

“They are considered twins. When they were little they always wanted to be together and this helped the adults a lot.”

Now both 23, Caterina Alagna and Melissa Fodera are basically twins. They were told about the fateful mix-up at age 8 and have been inseparable.

“We are a phenomenon,” Caterina acknowledged. “We have eight grandparents, two fathers, and two mothers.”

Far from taking a toll on the families, the arrangement has worked out beautifully.

“It seemed like a game and today neither of us have any memory of life before we were three,” Melissa said.

“Growing up I had Marinella as a second mother, as she still is.”

“At first, loving Melissa, my biological daughter, felt like betraying the daughter I had raised,” Gisella said, “but today Melissa and I truly feel like mother and daughter.”