Neil Lupin/RedfernsThe cause of Prince‘s sudden death last Thursday at age 57 has yet to be revealed, but sources tell People magazine the entertainer once had a history of using the prescription painkiller Percocet.

Prince’s longtime lawyer, L. Londell McMillan, however, has insisted that the singer was “not on any drugs that would be cause for concern.”

Though the performer was thought to have avoided recreational drugs, sources tell the entertainment magazine that he may have used the highly addictive drug to treat ongoing pain from his years of onstage performances, which had begun to take a toll on his body.

“His hip bothered him from jumping off risers for 20 years,” musician and ex-girlfriend Sheila E. tells People.

Surgery may not have been an option for Prince, who was a Jehovah’s Witness, the magazine suggests, since the religion prohibits its followers from accepting blood transfusions.

Meanwhile, Brown Mark, a former member of Prince’s band The Revolution, posted a video on his Facebook page revealing that he and fellow bandmates Bobby Z., Wendy Melvoin, Lisa Coleman and Matt “Doctor” Fink will reunite for tribute shows later this year in honor of the late entertainer.

“We have decided after spending three or four days together now grieving over the loss of Prince that we would like to come out and do some shows,” Melvoin said on behalf of the band. “We want to let you know that we’ll be there soon, so we want to let you know now.”

No official schedule or locations have been announced.

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