Gus Ruelas / Invision/AP 1 / 5
Gus Ruelas / Invision/AP 1 / 5

Though Bret Michaels's condition has been upgraded to stable, a source close to the family of the 47-year-old Poison frontman and "Celebrity Apprentice" contestant tells ET that Michaels will soon be undergoing surgery to relieve swelling around his brain.

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Michaels' father, Wally Sychak, told Access Hollywood that his son was "speaking slowly" when they last spoke on Saturday and that he was beginning to show signs of improvement.

In addition, Sychak said he had been told the rocker-turned-reality star is now "moving his arms and hands."

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A rep for Michaels told Access on Tuesday that the star "remains in ICU but [is] stable. They are running more [tests]." Doctors still have not located the source of the bleeding.

Some believe it was an accident last June at the Tony Awards, where he collided with a set piece while performing on stage, that may have led to the problem.

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