Following an angry response from some audience members at the January 2016 Sundance premiere, a few festival reviewers purposefully spoiled the film in detail so as to deter animal lovers from seeing the film.
Heather Matarazzo turned down a possibility to reprise her role of Dawn Wiener from Welcome to the Dollhouse (1995). She was replaced by Greta Gerwig.
Brie Larson had filmed a scene for the film, but it was deleted from the final cut.
According to director Todd Solondz, the title character was portrayed by four dachshund show dogs but personally found them to be "dumb".
Keaton Nigel Cooke learned "Clair De Lune" by Debussy on flute for a scene in less than one week.
Keaton Nigel Cooke is the only lead actor with two movies in this year's Sundance Film Festival (2016).