Alessia Cara had a sinus infection when she recorded the demo version of "I Choose," causing her voice to sound hoarse and shaky. She apologized for this before sending it in, but was surprised to find the directors loved it, as in the film, Cara's character sings the song during a snow storm, and would rightfully sound weaker. The demo version Cara was so nervous about ended up being the final version in the film.
As revealed in a 2017 interview with Jimmy Fallon, one of Alessia Cara's lifelong dreams was to be a voice in an animated movie. Producers of this film saw the interview and contacted her almost immediately after.
Tim names the baby "Ruth" as they drop her off at a candy factory. A Baby Ruth is a chocolate bar.
Although they're never revealed in the film, the first names of the parents are Walter and Helga Willoughby.
It is based on the book of the same name by Lois Lowry