The 36-year-old appeared on TalkTV's flagship evening news program, The News Desk, on Thursday where he was quickly asked by anchor Tom Newton Dunn about his father's ailing health.
WATCH: Sharon and Ozzy Osbourne ask for help
"He's doing well. I spoke to him shortly before coming in. He just says hello. I'll save the colorful language, but he says it sucks," Jack revealed.
Jack's appearance on the show came shortly after his mom, Sharon Osbourne, revealed she would be jetting back to the US to be by her husband's side after confirming his positive diagnosis.
"Ozzy was only diagnosed in the middle of the night our time. I spoke to him and he's OK. I am very worried about Ozzy right now," she said in an emotional interview with TalkTV on Thursday.
Ozzy has been diagnosed with COVID-19
She continued: "We've gone two years without him catching Covid and it's just Ozzy's luck it would be now."
The news means that Sharon will not be able to present her new hour-long panel debate show, The Talk, which airs Monday to Friday. Talking about returning to the show, Sharon said: "I can't believe my luck. I'm missing the show and I've only been there three days.
"I can't believe it. Three days and I'm missing the show but I will be back. I know I will." She concluded: "It will take me a week to get my old man back on his feet again and I will be back."
Jack revealed his dad is 'doing well'
The news comes after Sharon opened up about other health issues plaguing her husband.
The Black Sabbath frontman was diagnosed with Parkinson's Disease in 2003 but has had to endure several more health problems since, including a potentially deadly staph infection in 2018, pneumonia, and debilitating mobility injuries suffered during a fall inside his Los Angeles home in 2019, which resulted in multiple back and neck surgeries.
Sharon flew back to LA to be with her husband
Sharon revealed that Ozzy has "one more operation" before he can return home, alluding to their reported move back to the UK.
Appearing on Piers Morgan's new TalkTV show Uncensored before Ozzy's latest health woes, Sharon said that her husband of nearly 40 years is "doing okay".
The News Desk, TalkTV, 7pm Monday - Friday (Sky 526, Virgin Media 627, Freeview 237, and Freesat 217) and live and on demand on the TalkTV app and at Talk.TV.
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