Olympic gymnast Mary Lou Retton making 'remarkable' progress in ICU

U.S. Olympic gymnastics legend Mary Lou Retton is making "truly remarkable" progress in her fight against pneumonia, her daughter shared in a new update.

In an Instagram post, McKenna Kelley said her mom remains hospitalized in the ICU, but "her path to recovery is steadily progressing."

"Her fighting spirit is truly shining!" the post continued.

The 55-year-old decorated athlete had been admitted to a hospital ICU after falling ill with a "very rare form of pneumonia," Kelley said in another post about a week ago.

Retton's daughter didn't disclose details of the illness out of "respect for" Retton's "privacy," but she had said her mom wasn't able to breathe on her own.

Kelley also shared that her mom was uninsured and asked her followers to help "in any way" with hospital bill expenses , and included a link to a fundraising page. The SpotFund's goal was $50,000, but as of Monday, it has raised more than $439,000.

In Kelley's update, she extended "heartfelt gratitude for your overwhelming love and support," while sharing Retton's breath has become much stronger, with a "diminishing" reliance on machines.

SEE MORE: US Olympic gold winner Mary Lou Retton 'fighting for her life' in ICU

"Prayers have been felt and are being answered," Kelley's post said. "Though it's a lengthy journey, witnessing these improvements is incredibly heartening! She's beginning to respond to treatments."

Retton became a household name after her run at the 1984 Olympic Games, where she became the first American female gymnast to win the all-around gold medal and walked away with more medals than any other athlete competing, with five medals in total. She was just 16 years old at the time, and went on to be inducted into the United States Olympic and Paralympic Hall of Fame the following year, and the International Gymnastics Hall of Fame in 1997.

Retton went on to appear in TV and film roles and serve on the President's Council for Physical Fitness and Sports under President George W. Bush.