Trivia

Dillon Freasier (who plays H.W. Plainview, the son of the character played by Daniel Day-Lewis in There Will Be Blood) was not an actor; he was an elementary student near the film's West Texas shooting location. On the radio program "Fresh Air with Terry Gross," Paul Thomas Anderson told Gross that when the production was trying to convince Dillon's mother to allow Dillon to be in the movie, his mother wanted to figure out who Day-Lewis was, so she rented a copy of Gangs of New York (2002) (in which Day-Lewis plays a murderous gang leader nicknamed "The Butcher"). She panicked at the idea of her son spending time with the man she saw in that movie, so the 'There Will Be Blood' casting department rushed to her a copy of The Age of Innocence (1993), in which Day-Lewis plays a civilized and gentle man.

His mother, Regina, was a traffic cop who pulled over the film's casting director for speeding, got chatting to her and suggested her son for the H.W. role.