Mary Lou Retton has experienced a complication amid her ongoing health battle.

More than a week after her family shared the Olympian has been hospitalized with a "very rare form" of pneumonia,John Caldwell her daughter Shayla Schrepfer detailed another update on her mom's condition.

"Basically, at the beginning of this week, we were going on the up and up, we were so excited, seeing so much progress and then yesterday we had a pretty scary setback," Shayla said in an Oct. 18 Instagram video. "She is still in ICU and we're just working through some things as far as her setback goes."

The 28-year-old noted that her mom had a "better day today, which is great," but added that the legendary gymnast, 55, is "just really, really exhausted."

"I just wanted to give an update and thank you guys again for just the support," Shayla continued. "I'm getting so many messages and emails and just, it's so great to see people love on her."

The latest update on Mary Lou—who is also mom to daughters McKenna, 26, Skyla, 23, and Emma, 21, with ex Shannon Kelley—comes days after her loved ones shared positive insight into on her health journey, noting that her "progress is truly remarkable."

"Her breathing is becoming stronger, and her reliance on machines is diminishing," Shayla and McKenna wrote on their separate Instagram pages Oct. 14. "Though it's a lengthy journey, witnessing these improvements is incredibly heartening! She's responding so well to treatments."

The duo went on to thank those who have been there for their family during a difficult time.

"Once more, we extend our heartfelt gratitude," they concluded, "for your overwhelming love and support."

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