<P> Charlie's integration also made her a voice for the audience and critics of Gossip Girl . TV Fanatic warmly welcomed her character, stating that she "good - naturedly mocked the show and its often convoluted plot lines ." DeFer would later reveal details behind her character's involvement in the fourth season finale, "As far as I know I'm just in the next five episodes until the season finale, and then I have no idea . But I really hope we get the opportunity to finish what Charlie started as I think it's going to be a story - line that people will really want to follow ." DeFer also states that Charlie is more relatable in comparison to other characters that have appeared in the show . "She is such a real person, not being from that life and what not ..." </P> <P> The character is first introduced in the second half of season four as Charlotte "Charlie" Rhodes, the estranged cousin of Serena and Eric van der Woodsen . Under the guise of Charlie Rhodes, she experiences the world of the Upper East Side, becoming particularly close with Dan Humphrey, though Dan puts a stop to the budding relationship because of his history with Serena . However, upon learning that Vanessa Abrams had intentionally sabotaged a meeting Charlie had organized, Dan allows himself to become closer to Charlie while severing his ties with Vanessa . </P> <P> The two then begin an awkward relationship which concludes in the season's penultimate episode when Charlie, dressed like Serena, demands that Dan call her by Serena's name . It is later revealed that Charlie suffers from bi-polar disorder and she has stopped taking her medication . She leaves the Upper East Side and meets up with her mother, Carol . In the season's final moments, "Charlie Rhodes" is revealed to be Ivy Dickens, an aspiring actress that Carol hired to gain access to her daughter's trust fund . In her final scene she puts a napkin with Georgina's number in her bag which hints that the two will team up in the fifth season . </P> <P> With regard to her involvement in the finale, DeFer discussed her character's involvement . "Charlie has a great deal to do with the season finale...but what I am allowed to say is that Charlie does mix it up with every character ." </P>

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