"He gets shot in the head ... multiple times," UsMagazine.com quoted Pitt as saying at the R-rated film's New York premiere Monday night. "I don't know what that says about me as a parent."
Pitt said Maddox and his 9-year-old son Pax "have already seen [the movie] and they love it."
Pitt also has four younger children with his fiancee, actress Angelina Jolie.
Celebrity Breakups and divorces of 2014 [PHOTOS]