Just because you play brother and sister on the same television show doesn't mean you can't date in real life. At least that's how Michael C. Hall and Jennifer Carpenter appear to feel.
The two are co-stars of the show "Dexter" in which Hall plays a crime-solving serial killer and Carpenter plays his detective sister with a Daddy complex. The on-set siblings have a different relationship off camera. According to People.com, the two are dating.