John Cameron Mitchell was attracted by the script, and by the personal fact that at 14, he lost his 10-year-old brother to a heart problem; "It was a sudden, unexpected event. It defined a family forever and recovering from it was something we're still doing."
Nicole Kidman didn't see the the original Broadway play when it premiered in 2006, but she read a review and called up a producer from her production company, Blossom Films. The following night he saw the play and afterwards set up a meeting with David Lindsay-Abaire about the film. Kidman later read the script and saw an Australian production.
Miles Teller became good friends with Nicole Kidman and her husband Keith Urban during production. Following this, in 2016, Teller was once spontaneously invited to join Urban on stage during his show in New Mexico to duet on The Temptations' "My Girl". This marked Teller's first time singing for a live audience.
Nicole Kidman and Aaron Eckhart both started in movies in the Batman Franchise. Nicole Kidman played Dr. Chase Meridian in Batman Forever (1995), and Aaron Eckhart played Harvey Dent/Two-Face in The Dark Knight (2008).