Parents Maria and Andrew Petti were driving from their home in Farmingdale to the hospital on Feb. 15, but Mikayla wouldn't wait.
"Mikayla arrived inside my pant leg," Maria told Good Morning America. "We got to the hospital; my husband ran inside and said, 'My wife had a baby in the car.'"
Born at just 24 weeks, she only weighed 1-pound-8-ounces and wasn't breathing well. Her heart rate was not in the normal range.
Dr. John Mathew at Saint Joseph Hospital carefully pumped oxygen into her tiny, paper-thin lungs for more than an hour to allow her to breathe.
WATCH: NICU nurse caring for baby also cared for father 33 years ago at New Jersey hospital
NICU nurse caring for baby also cared for father 33 years ago at New Jersey hospital
The hospital was not equipped with a NICU nursery. Mikayla was placed in an infant warmer and Dr. John Mathew at Saint Joseph Hospital carefully pumped oxygen into her tiny, paper-thin lungs for more than an hour to allow her to breathe.
"It was a miracle that she's here with us, this cute little baby girl, but she's a little fighter, so you know I'm happy to see her smiling," Matthew said.
Once she was stable, she was taken to another hospital for further treatment. She spent the first 122 days of her life at the hospital.
"They are amazing people and what they do every day - the emotional and physical support to the families, to caring for these babies like their own, it has left a lasting impression on us," Maria said.
Due to the pandemic, NICU visitations eventually became limited to one parent a day for one hour. The Pettis held Mikayla for the first time 10 days after she was born.
After a heart surgery and tons of love, Mikayla now weighs 9-pounds-3-ounces, and she is thriving.
"She rolled over for the first time," Petti told GMA. "She's defying all odds of what a micro preemie baby should be doing."
On Aug. 5, the Pettis brought Mikayla back to the Saint Joseph Hospital to meet with the doctors and nurses who saved her life.
Maria said she owes everything to those doctors and hopes they get all the honor they deserve.
She also said she hopes her daughter will consider a career as a NICU nurse when she grows up.