It was supposed to be a quick shopping trip to the Walmart Neighborhood Market on Babcock Street in Melbourne just before noon Thursday.
Police say a pregnant woman and her three daughters were waiting in the car while the father went into the store to grab a few groceries.
While he was inside, the mother's water broke, police say, and when the soon-to-be father came outside, he saw his children yelling for him to hurry to the car.
Police told WKMG-TV the father was only inside for a few minutes, but in that short amount of time, the mother had given birth to her fourth child in the car.
"Oh, my God. I wouldn't know what to do. I guess it would be an experience," says C.J. Ahrens.
"Wow, what an experience," says Brenda Baker, a mother of two.
Paramedics were called to the Walmart, but were only used to transport the mother to Holmes Regional Medical Center, just a few miles down the road.
The news that a baby was born in the parking lot quickly spread around the Walmart as the day went on, but what shocked folks the most was the fact that the woman gave birth in front of her three children.
"I would not go out if I was expecting," says Baker.
Walmart says they're going to be giving the family some gift cards and care packages.
The mother and her baby boy are doing well, officials say.