Olympic gymnast Mary Lou Retton is looking back on the terrifying series of events that led to her month-long stay at an intensive care unity (ICU) last fall, after she fell ill with a rare and life-threatening case of pneumonia.

"Things just went south really, really fast," Retton's oldest daughter, Shayla Schrepfer, recounts in a new sit-down with NBC's TODAY. Their conversation was filmed at the retired gymnast's home in Boerne, Texas.

Retton's decline began suddenly, after she and Shayla met for a manicure date one day in the fall of 2023. Retton is mom to four adult daughters in total, and she was planning a "girls' trip" to Houston with Shayla and her sisters. Shayla noticed her mom seemed tired while they were getting her nails done -- Retton commented that she was "so tired" and couldn't "keep my eyes open" -- but didn't think much of it at the time. The next day, however, Retton's symptoms were too severe to be ignored. She missed her trip to Houston, and instead, a close neighbor found her collapsed on her bedroom floor, awake but struggling to breathe.

"She came in the house. She knows my code, and saw me and found me," Retton remembers, explaining that her neighbor -- named Magda -- grew concerned after seeing that one of the cars in the driveway had a door open. "And Magda pretty much saved my life."

Retton was taken to a local hospital, but aside from offering her a pneumonia diagnosis, that facility failed to provide answers. "It was a bad experience," she admits. "I wasn't being treated."

After a couple of days, Retton was sent home -- and one day later, she was almost unresponsive once again. This time, Shayla found her, and immediately took her to a different hospital, where her blood oxygen levels yielded a dangerously low reading. Retton was admitted the ICU, and after a week of scrambling to figure out what was wrong, doctors told her daughters to brace for a bad outcome.

"They literally said...you need to get your sister here," Shayla remembers. "Because we don't know if she's gonna make it through the night. So McKenna and I, we put our hands on her and we said a prayer."

"They were saying their goodbyes to me," Retton adds. "I just remember loving on you and giving you a hug," Shayla adds. "McKenna kept saying things like, 'It's okay, you can go.'"

But a last-ditch treatment effort proved to be nothing short of miraculous. After doctors decided to try pumping oxygen through her nose, Retton slowly began to recover. Shayla jokes that unlikely turnaround is on brand for her Olympian mother.

"She's the one in a million that wins the Olympics. But she's also the one in a million that will get some rare form of pneumonia that you have no idea what it is, but she'll make it through," she says.

As for Retton herself, she's well aware of the long road ahead of her -- but grateful for the small blessings that have come with her recovery, like getting to leave the ICU after a month-long stay and come home in time for Christmas.

"I don't know how long I'll indefinitely need the oxygen. But you have no idea how blessed and how grateful I was for this holiday season," she says. "...I mean, when you face death in the eyes -- I have so much to look forward to. I'm a fighter, and I'm not gonna give up."

Who is Mary Lou Retton?

Anyone over 40 likely knows of Retton and her accomplishments, but those younger can consider her the original Simone Biles. Her win at the 1984 Summer Olympics was as dramatic as it was improbable. She'd just had knee surgery a few weeks before the games and need perfect 10 scores on the final two individual events to beat Szabo by 0.05 points.

After the Olympics, Retton would continue to compete until her retirement from the sport in 1986. She'd then become a popular spokesperson for various products, attend the University of Texas and eventually get into sports broadcasting.

Her most recent high-profile TV appearance was in 2018 when she was on Dancing With the Stars. Country radio host Bobby Bones would win that season.

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