ELIZABETH HURLEY, BILLY BALDWIN AND NEW YORK SOCIAL DIARY’S DAVID PATRICK COLUMBIA GUEST STAR — Blair (Leighton Meester) feels like her Upper East Side status might be slipping away and devises a plan to assure that doesn’t happen. Meanwhile, Lily (Kelly Rutherford) throws a family gathering – including William (guest star Baldwin), Carol (guest star Sheila Kelly) and Lola (guest star Ella Rae Peck) – in an attempt to prove the van der Woodsen family is as united as ever. Finally, Nate (Chace Crawford) digs into Diana’s (guest star Hurley) past and is surprised by what he discovers. Blake Lively, Penn Badgley, Ed Westwick, Kaylee DeFer and Matthew Settle also star