The Masked Singer judge revealed that the 30-year-old is "still unwell" and unable to leave her bed after she was diagnosed with the chronic condition, which causes long-term pain and fatigue all over the body, and for which there is currently no cure, according to the NHS.
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Appearing on Friday's Loose Women, Jonathan said when asked about Betty's wellbeing: "My daughter is still unwell at the moment and is bedridden. It is difficult."
Trying to remain "optimistic" about her condition, the 60-year-old added: "There isn't a cure as such or quick fix. I'm a very optimistic person. There are so many people going through so much worse and she's not dying. We are lucky. We know she is safe."
In typical Jonathan fashion, he cheekily added: "I wish I didn't have to look after her dog though. He's a right weirdo."
Jonathan with daughter Betty in November
Jonathan revealed Betty's diagnosis last October, explaining on Good Morning Britain that he was cancelling his annual Halloween bash because of her illness.
He told presenters Richard Madeley and Ranvir Singh: "One of our children isn’t well, one of our children had Covid at the beginning of the pandemic and they thought she had long Covid, but it's now been diagnosed as fibromyalgia which is quite debilitating, so she's back home with us and we're looking after her."
Betty opened up about her diagnosis on Instagram
Betty originally opened up about her diagnosis in a post on Instagram. "Fibromyalgia? I hardly know her!" she wrote in a caption.
"This is me letting y'all know I got a Fibromyalgia diagnosis. Shout out to the 4 people who all said they thought I had fibro, turns out y'all were right. There's always a lot of weird feelings that come with a new diagnosis, but this one overall feels like a relief.
"It feels like my pain is being acknowledged, and that with this diagnosis I can better find ways of managing my pain."
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