*Members of the Jackson family are irate over a new claim by Michael’s former best friend and doctor Arnold Klein that the King of Pop was gay and had a relationship with his office manager Jason Pfeiffer.

Pfeiffer, according to TMZ, did a television interview last week claiming he had sexual relations with Michael. Also, Dr. Klein told the Web site that he once walked in on the two men with their shirts off.

Michael’s father Joe Jackson and brother Jermaine have fired back against Klein’s allegations. Papa Joe told TMZ “It’s not true. Michael was not gay. [Klein’s] a doctor and knows better than to break his vows against a patient.”

Jermaine told TMZ: “Arnold Klein? F*** him. He’s full of s***. Michael was not gay.”