In an interview with NPR’s Terry Gross, Alan Ball shed some light on some of the goings-on behind the scenes at Six Feet Under and a few of the character details left unanswered after the show’s finale. He confessed that the writers had almost brought brother and sister Billy and Brenda together sexually but eventually let their relationship exist in its creepy limbo. He also says that it was never certain Nate was Maya’s biological father. TV Squad offers up a few more insights.