Los Angeles Dodgers star Freddie Freeman and wife Chelsea have had the "hardest and scariest days of our lives" this week.

The couple announced on Instagram that their 3-year-old son, Max, has been diagnosed with a "severe case" of Guillain-Barré syndrome, which is "especially rare in children."

The condition involves the immune system attacking nerves, causing muscle weakness.

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Freeman family

National League first baseman Freddie Freeman of the Los Angeles Dodgers with wife Chelsea during the Red Carpet Show at L.A. Live.  (Gary A. Vasquez/USA Today Sports)

The couple detailed their frightening ordeal in a joint post.

"Last Friday, Max rapidly declined and went into full body paralysis," the couple wrote. "We are very fortunate to have gotten him to the hospital in time so they could reinforce his lungs. Freddie was in Houston at the time and rushed to the first flight back home … 

"These have been the hardest and scariest days of our lives. Maximus is such a special boy and he has been fighting SO hard. This is going to be a journey to recover, but we have faith that he will be completely healed."

The Freemans say their son has made "improvements in the last 48 hours" that they were "blown away by."

Freddie Freeman runs bases

Freddie Freeman of the Los Angeles Dodgers runs the bases after a home run during the sixth inning against the Kansas City Royals at Dodger Stadium June 16, 2024, in Los Angeles.  (Katelyn Mulcahy/Getty Images)

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"Maximus was excavated from his breathing tube and taken off of the ventilator yesterday, which is a huge win for us," they wrote.

"We believe in the power of prayer and we have been witnessing a miracle in his recovery. Please continue to cover Maximus and our family in your prayers. We really appreciate and have felt all of your support."

Max has two older brothers, Charlie and Brandon, the latter of whom is six weeks older than Max, having been born via surrogate.

Freddie Freeman runs the bases

Freddie Freeman of the Los Angeles Dodgers doubles in the fourth inning during the 2024 Seoul Series game against the Kiwoom Heroes at Gocheok Sky Dome March 17, 2024 in Seoul, South Korea. (Mary DeCicco/MLB Photos via Getty Images)

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Freeman is in his third season with the Dodgers after spending his first 12 seasons with the Atlanta Braves, winning the World Series in his final game with them in 2021. He signed a six-year deal with LA.

He is hitting .288 with an .888 OPS.

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