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Bret Michaels continues to remain in critical condition after suffering a brain hemorrhage last Thursday, his rep tells

"There's a rumor out there that Bret passed," says the rep. "It isn't true."

Sharon Osbourne, Michaels' costar on NBC's Celebrity Apprentice, has known the former Poison front man, 47, for 30 years.

What's happened to him is "just hideous," she told Monday at the NBC Universal Summer Press Day in Pasadena, Calif. "It's devastating, and it makes you feel all these different feelings. Your heart goes out to his family, your heart goes out to him. He's the nicest guy in the world. And then you start thinking about your own mortality. You start thinking, Oh my God. It just makes you appreciate how lucky we all are."

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The last time she saw Michaels, he was in good health. "Absolutely he was," she told Us.

On Monday, Donald Trump -- who claimed to be in touch with people at the hospital where Michaels is being treated -- remarked that the rocker's prognosis wasn't "great."

Appearing on the Today show Tuesday morning, he had no updates but was praying for the best.

"He's such a good guy," he said. "I just hope he makes it."