 They were largely homeschooled as a child, with the exception of three years of high school, and obtained a GED.In 2001, at age six, they were cast by filmmaker Richard Linklater to play the title character of sorts of the film "Boyhood"; Linklater wanted to make an unprecedented film that would show a boy's coming of age, but with the actors growing up or aging on screen.Coltrane and other members of the cast were filmed intermittently for several days at a time between May 2002 and August 2013, when they turned 19; there were 45 days of filming altogether.