Keith Kupferer and Tara Mallen, who play husband and wife Dan and Sharon Mueller, are married in real life, and Katherine Mallen Kupferer is their actual daughter.
The title of this movie, "Ghostlight," refers to a theatrical tradition that calls for a single bulb to remain lit on a stage even when the rest of the theater is literally (and figuratively) dark. The origins of this tradition are unknown; it may have emerged from basic safety concerns, but since theater has numerous superstitions, many of obscure origins, it may be only or primarily a symbol for luck. Some members of the general public were first introduced to this tradition when theaters worldwide were forced to close during the COVID-19 pandemic and there were several articles published and news pieces produced about theaters keeping or reinstating the ghost light tradition until performances could resume; for example, a CBS news piece about the Broadway shutdown was titled "Ghost Light: The Year Broadway Went Dark."
Keith Kupferer actually played Jud in his high school's production of Rodgers and Hammerstein's "Oklahoma".
The song "That's Enough" that Sharon's elementary school class sings in the film's opening half hour was written by the musician Sad Brad Smith, the stage name of actor Bradley Grant Smith. Smith portrays Jim in this film.
The prop dagger used for Juliet's death scene is a plastic retractable dagger that producer Ian Keiser purchased off Amazon before preproduction began.
Deanna Dunagan: As the woman who greets Daisy in the bathroom mid-performance. Dunagan won a Tony-winner for the premiere Broadway production of "August, Osage County" in 2008. The character she plays is credited as "Tony-Winner Deanna Dunagan."