The producers of the film did not include a trailer on location for Maureen O'Hara in their budget. John Candy was furious that the producers were showing someone of her stature such disrespect, and he gave her his own trailer. The producers finally caved in, because they couldn't have Candy, the star of the film, without his own trailer.
During filming, Maureen O'Hara would often tell John Candy that he reminded her of Charles Laughton, citing that underneath the clown character, had existed a powerful, complicated actor. She told him to trust his talent as an actor, and not always play the clown.
Practically the entire crew that worked on this film worked on Maman, j'ai raté l'avion ! (1990) and Maman, j'ai encore raté l'avion ! (1992).
Chris Columbus wrote the script with Maureen O'Hara in mind for the role of the mother. Once casting had begun, he insisted on having O'Hara play the role, and began a search for her. What he didn't know was that she had long since retired, and was living on St. Croix in the U.S. Virgin Islands. Knowing her brother Charles B. Fitzsimons was still in the movie industry, Columbus contacted him, and had a script sent. O'Hara's brother then sent the script to her and said, "This you do!" After reading the script herself, Maureen contacted her brother and said, "This I do!"