<P> Dr. William van der Woodsen, portrayed by William Baldwin in seasons three, four, five and six, is Lily's first husband and the father of Serena and Eric . Lily hides the fact that she has cancer from her family except her mother and goes to her ex-husband for treatment . When Rufus finds out, it causes a strain in their marriage . Meanwhile, Serena is angry with Lily for concealing this from her since Serena had been searching for her father for these past 3 years . When William comes back to the Upper East Side, he is met with hostility from his family . Lily decides that she needs him; Eric is cautious about his agenda, Serena decides she wants to get to know her father; and Rufus is angry at his intrusion . Although William really had been treating Lily, he continues to keep her just sick enough for him to be needed because he had fallen in love with her again and misses his family . Jenny wanted her Humphrey family back and the rest of the family finds out William's plot to separate Lily and Rufus . When Serena finds out, she is especially devastated, and William leaves town as the police closes in on him . He returns in season four when Lily is arrested to support his family . He also makes amends with Rufus . In Season 5, William van der Woodsen returns to the Upper East Side for the wake, and is the executor of CeCe's estate . Ivy Dickens is announced as CeCe's heir and we learn that CeCe was apparently aware the whole time of Ivy's real identity . Carol Rhodes also reveals the identity of Charlie's father as William Van der Woodsen . In season 6, it is shown that William is in a relationship with Ivy, the two seemingly working together for a plot to take Lilly down . When Bart Bass dies, William consoles Lilly about it and the two rekindle their old love . Ivy is confused when she is ready to tell Lilly about them and William claims to have never met Ivy before . In private, William reveals to Ivy that he was using her all along in a plan to get back with Lilly and coldly dismisses her . The final moments of the series reveal that William and Lilly have remarried . </P> <P> Portrayed by Florencia Lozano in the pilot and Margaret Colin since episode four, Eleanor Waldorf is the fashion designer mother of Blair Waldorf . Her decades - long marriage to Blair's father, Harold Waldorf, ended when Harold left her to pursue a relationship with a French male model, Roman . It is implied through flashbacks that Eleanor knew about Harold's sexuality . Her clothing line' Eleanor Waldorf Designs' is being distributed by Barney's and Bendel's . She once employed Jenny as an overworked intern . She later marries her divorce attorney, Cyrus Rose . </P> <P> Portrayed by John Shea in seasons one, two and five . Harold Waldorf is Blair's father who went to France to live with his male lover Roman . He traditionally makes pumpkin pie during Thanksgiving but hasn't made it since Blair's last Thanksgiving with him, before he came out and left for Europe . He returns for the holidays with his partner, Roman, a model once used by Harold's ex-wife, Eleanor . Roman earns Blair's spite during Christmas by breaking his leg, inviting an old flame of Roman's that frustrates Harold . Harold speaks with Blair about the incident and then shows her his life in France through a video . He now lives in France, tending a vineyard and has a cat named Cat, the same name as the cat in Blair's favorite movie, Breakfast at Tiffany's . He returns in the second season during Thanksgiving when Blair first thought that her mother didn't invite him . He and Blair share a pie during thanksgiving . He gives Blair a bulldog named Handsome Dan whom Blair renames Handsome . During Blair's hazing incident that sparked a controversy with Miss Carr and Dan and the almost removal of Gossip Girl's blog, Blair convinces her father and the parent's council of Constance - St. Jude's by showing a picture of Dan in a compromising position with Miss Carr, thus securing her admission to Yale . When he overhears Blair's conversation about the picture only being eerily prophetic and untrue, Harold speaks with Blair and tells her that he saw a different side of her and is disappointed that he lied for her indirectly . He then tells Blair that the college she is admitted to doesn't matter and that the person she becomes matters more . </P> <P> Portrayed by Michelle Trachtenberg in seasons one till six, Georgina Sparks is a ruthless, manipulative girl from Serena's past who returns to New York City in the final episodes of season one after escaping drug treatment in Utah . Before that, she was supposed to be at an Equestrian circuit but sold her show pony for cocaine, prompting her parents to send her to rehab . Being Serena's friend, she wants Serena to be back to her old self and join her in doing things they used to do together . Her sudden return causes Serena to relapse into her old habits and even fixes Serena's drink which causes her to wake up late for her SATs . After Serena asks that she leave Manhattan, she becomes even more determined to ruin her life . Georgina persuades Dan to almost sleep with her, but this leads to a confrontation with Serena . Blair, taking matters into her own hands, informs her parents of her location, persuades Dan to make Georgina fall for Blair's trap and is sent to a reform school recommended by Blair herself . She reappears late in the second season where Georgina is at a church camp and appears to be a completely reformed "saved" Christian . That is, until Blair persuades her to help them in a plot to take down Poppy . After which, Georgina goes back to her old scheming ways . At the end of the second season, she is about to attend NYU and requests Blair as her roommate . She reappears in the first few episodes of the third season and surprises Blair Waldorf when she shows up as her lovely roommate . After her relationship with Dan is once again thwarted, followed by blackmailing Vanessa and ruining Rufus and Lily's wedding, she gets tricked and sent away with a Russian prince, a plan to get rid of her set by Blair and with the assistance of Dorota, by exiling her to Europe . At the end of season 3, after a long absence, Georgina returns to New York City from her enforced exile in Belarus disguised by wearing a blonde wig and a large coat, desperately seeking the help of various Upper - East Siders with her "problem". It is revealed that Georgina is pregnant, and claims it is Dan's child . At the start of season 4, she runs off again, leaving Dan with their son Milo but it is later revealed that he is not the father and that it was just another one of Georgina's schemes . Georgina takes Milo back when Dan signs the birth certificate, ending her manipulative plot and leaves Dan . Georgina later returns at the very end of season 4 for the Constance Billiard alumni event in hopes of stirring up drama . She reveals to Serena and others in attendance that she is currently living in Bedford, New York, is married to a young Wall Street stockbroker intern, and is outright bored with her current lifestyle of being a stay - at - home - mother . Georgina accidentally learns the secret behind Serena's cousin Charlie and informs her to keep in touch . In Season 5 at Blair's wedding, it is revealed that Georgina steps in as the' new' Gossip Girl, the anonymous narrator of the series, as the' real' Gossip Girl' abandoned her post following Chuck and Blair's accident . In the season 5 finale, it is revealed that she will help Dan write his follow up to "Inside". Having left him for Chuck, Dan promises to write the book that he should previously published, which Georgina, who has her own score to settle with the Upper East Side, is more than happy to help him with . In the series finale, she is shown to be in a relationship with Jack Bass and helps Blair and Chuck with their problem regarding Bart Bass . </P>

Who plays blair's dad on gossip girl