Over the weekend, it was reported that the 60-year-old TV mogul had been rushed to hospital with a broken back, after falling from an electric bike he was riding at his home in California.
Having now undergone surgery on his back, reports have suggested that Simon has already been up walking, which his AGT co-star Heidi Klum appears to have confirmed.
Speaking to People magazine, she revealed: “We were told he already got up out of the bed, which is just incredible.
“When we woke up on Sunday morning to the news, you think, ‘Oh my gosh, will he ever walk again?’”
The supermodel continued: “Who knows maybe next week he will be sitting there with us again, at the speed he’s going! I hope he does.
“I was like, ‘What else is happening?’ Every morning you wake up to another crazy news and I hope this is it for now. Can we just turn the page and can life get better? We’re all hoping for that.”
While Simon recovers from surgery, he has been temporarily replaced on the AGT judging panel by Kelly Clarkson, who he previously judged on the very first series of American Idol.
Simon spoke out for the first time about his injury on Monday morning, joking: “Some good advice… If you buy an electric trail bike, read the manual before you ride it for the first time.”
He added: “I have broken part of my back. Thank you to everyone for your kind messages. And a massive thank you to all the nurses and doctors. Some of the nicest people I have ever met.”