September 11 will always be a day to remember and honor, but it's also a date that marks the birth of one of comicdom's most beloved female villains ever... Dr. Harleen Frances Quinzel, aka Harley Quinn! That's right, DC Comics own lovable Batman villain and The Joker's girlfriend celebrates her 20th Birthday this month, and to commemorate the occasion we look back at her decorated and insane history!
