Blake Lively, Leighton Meester, Penn Badgley, Chace Crawford, Ed Westwick, Kaylee DeFer, Kelly Rutherford, Matthew Settle

" Con Heir " is the 18th episode of the fifth season of the television series , which originally aired on April 2, 2012.

: It is revealed that William is the biological father of Lola Rhodes, the "real" Charlie Rhodes, making Serena and Lola half-sisters.

'Gossip Girl,' Season 5, Episode 18, 'Con Heir': TV Recap - WSJ

: Chuck invites his uncle Jack Bass back to town to thank him for a life-saving blood donation. However, the trip doesn't go as planned when Chuck discovers Jack couldn't have been the donor because he has Hepatitis.

Desmond Harrington (Jack Bass), William Baldwin (William van der Woodsen), Dick Cavett