“Partridge Family” star Danny Bonaduce is suffering from a mystery illness. Earlier this week, Celia Bonaduce, sister of Danny, revealed in a Facebook post that her brother’s balance “sucks” and that doctors could not give a definite diagnosis as to what was happening to her brother.

“Many of you have reached out to see what’s going on with my brother Danny. Thank you,” she wrote. “Along with Dairy Queen dipped cones and your messages, he is feeling the love.”

“We are not being coy when we say this is a ‘mystery illness.’ In layman’s terms, his balance sucks—super sucks—and all the great medical minds of Seattle are at work trying to solve this conundrum. We will keep you posted,” she continued.

She added that while Danny is a public figure, he is also her “well-loved brother,” urging her followers to type their comments accordingly.

On May 1, Danny took to Twitter to explain his decision to take a temporary leave from his show, “The Danny Bonaduce & Sarah Morning Show.” Sharing a screenshot of his sister’s post, he wrote, “Thank you for all of the well wishes. It really means a lot to me that so many of you have reached out. Just wanted to share something my sister posted on Facebook.”

Danny first announced his leave from his show on April 29, when he shared a photo of himself holding onto a cane. “Some news to share. I’m taking a temporary medical leave from my radio show. I’ll share more when I know more. I’m still working towards receiving a diagnosis. What I know is, I need time to focus on my health. I love my job and talking to you guys & I’ll be back on the air soon,” he wrote at the time.

In a separate tweet, he quipped that he’s joining the ranks of Charlie Chaplin, Willy Wonka and the likes because of his cane. “Charlie Chaplin, Willy Wonka, Danny Bonaduce, I’ve joined the club of cool guys with canes,” he wrote.

Danny first rose to fame in the early ’70s, when he played Danny Partridge on “The Partridge Family.”

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