We first learned in January that Black Sabbath's Ozzy Osbourne has been diagnosed with Parkinson's Disease. Now, Mötley Crüe's Nikki Sixx has given an update on Osbourne's reported health while battling the disease.

Nikki Sixx took to social media to share that Osbourne reportedly "isn't doing good" health-wise.

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After his Parkinson's diagnosis, Osbourne canceled his 2020 North American tour to focus on medical treatments. However, due to the ongoing COVID-19 pandemic, he was forced to cancel his medical trip to Switzerland.

Back in April, his daughter Kelly Osbourne shared that her father was in good spirits amid the pandemic. She also said that his recent treatments have greatly helped with his symptoms and overall progress. Following this, his son Jack Osbourne revealed that his father will likely retire "within the next five to ten years."

Last month, Osbourne gave a health update on his wife Sharon Osbourne's show The Talk. Along with his Parkinson's diagnosis, Osbourne says he is still recovering from surgery he had last year. The surgery was to repair an old injury he sustained during a 2003 ATV accident. As he continues to quarantine at home, he says the extra time has been beneficial for him.

"I’m getting better, it’s a slow process, but I’m getting there slowly but surely," he says. "It’s been good actually [quarantining], because I’ve been recovering from the surgery I had last year. I’ve never been at home this long in my whole career."

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Now, Nikki Sixx is giving an update on Osbourne's health. A fan asked him about Osbourne on Twitter. Nikki Sixx kept his response brief, but shared what he was told by someone.

At this time, no official statement or update has been released regarding Osbourne's health.

Osbourne's new documentary The Nine Lives Of Ozzy Osbourne arrives on A&E this summer. Produced by Jack Osbourne, the documentary shows the Black Sabbath vocalist's life and career throughout the years. The film will also show his struggles with his Parkinson's diagnosis and previous health issues. Directed by Greg Johnston, The Nine Lives of Ozzy Osbourne is the first documentary to be released about Ozzy in over ten years.

A sneak peek of The Nine Lives of Ozzy Osbourne is available to watch below.