Trained as an opera singer at a young age due to being born with a debilitating stutter. Enrolling in opera was inspired by their kindergarten teacher, within a year of opera training their speech impediment was gone. Miller said they had a 'breathe-line stutter and wasn't breathing in enough to complete a word and that opera vocal training is all about control and manipulation of the breath.
[on We Need to Talk About Kevin (2011)] My agent sent me the script and I went into a sort of wrathful, thirsting pursuit. I immediately became ravenous, and I just started pursuing it like a stalker.
