Michael Jackson's Son May Testify At The Star's Death Trial

Sources close to Prince tell TMZ ... the 14-year-old is "nervous" and worried that if he's called to the stand he might get flustered and "mess up."

We're told if Prince is called by prosecutors ... Katherine will ask her lawyers to request that the entire courtroom be cleared during his testimony. Judge Michael Pastor almost certainly will prohibit the media from training a camera on Prince, but it's unlikely he'll clear the courtroom.