A budding novelist and her film director husband, Kelly (Melanie Lynskey) and Jeff (Joe Swanberg) and their two-year-old son live a peaceful existence in Chicago. But when Jeff's irresponsible younger sister, Jenny (Anna Kendrick), comes to live with themafter a breakup, things start to change. Jenny begins a rocky relationship with a baby sitter-cum-pot dealer (Mark Webber), and she and a friend, Carson (Lena Dunham), instigate an evolution in Kelly's life, as her career and her relationship with her husband begin to grow in new directions. But are they welcome ones? In HAPPY CHRISTMAS, writer/actor/director Joe Swanberg (Drinking Buddies) explores both sibling relationships and the choices women face in young families. Using his unique improvisational technique, Swanberg creates a dramatic experience that results in a natural, relatable peek into his characters' lives, filled with an engaging warmth and the actors' own natural sense of humor.