May 1, 2009  file photo, Larry Birkhead arrives at the Barnstable Brown Derby party in Louisville, Ky., . Saying he wanted to avoid &quot;a circus sideshow,&quot; a judge barred prosecutors Thursday from asking a witness whether a sexual relationship existed between celebrity model Anna Nicole Smith and the woman psychiatrist accused of providing her with excessive medication. Larry Birkhead, the father of Smith&#39;s daughter, was ordered by the judge to be ready to be the next witness.