Sometimes they speak a language all their own, and sometimes they want nothing more than to make each other suffer. The sisters of movies past are often at odds—think Geena Davis and Lori Petty’s baseball rivalry in A League of Their Own and Cinderella’s cruel step-sisters. Occasionally they function as a team with a common goal, as do the scheming twins in The Parent Trap (played first by Haley Mills and later by then-newbie Lindsay Lohan). And sometimes they aren’t sisters in the literal sense—but as Whoopi Goldberg’s Sister Mary Clarence learns in Sister Act, blood ties aren't a prerequisite for sisterly love. (A shared love of gospel and ‘60s girl-group music, on the other hand, is.)
On Dec. 18, Tina Fey and Amy Poehler will be inducted into the sisterhood themselves with the release of the aptly titled Sisters, a comedy which finds them overcoming their differences in the service of an epic party in their soon-to-be-sold childhood home. In celebration of Fey, Poehler and their forebears, here’s a look back at the most memorable sisters in the movies.