(CNN) It was not weather or a mechanical problem that diverted a Spirit Airlines flight on June 22. It was the unscheduled arrival of an additional passenger, born midflight, that caused the plane from Fort Lauderdale to Dallas to make an unscheduled stop in New Orleans.

Cristina Penton was 36 weeks pregnant when she boarded Flight 971 with her 11- and 12-year-old kids in tow. Penton had carried those two children to full term, and she thought she was far enough away from the third child's due date to make the trip.

Soon after takeoff, Penton wasn't feeling well. She alerted the flight attendants and they went into action, making her comfortable and giving her free water, for which the budget airline usually charges.

Then the contractions started. Luckily for Penton, a pediatrician and nurse were also on the plane. Though they repeatedly told her not to push, Penton said her water broke and three pushes later her son had arrived. Her fellow passengers clapped when they heard the baby's cries.

"It went really, really quick. There was no time to prepare or land or do anything," Penton said. "He did what he wanted. We were all just along for the ride."

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