Early in the film's pre-production stages, Dustin Hoffman and Anne Bancroft were strongly considered for the roles of Beau Burroughs and Katherine Richelieu. But when Bancroft died, and Hoffman had filming commitments for several other projects, the roles were given to Kevin Costner and Shirley MacLaine.
The Screenwriter Ted Griffin was the original Director, but was fired after just twelve days of shooting, which resulted in Rob Reiner taking over. Production had to be shut down for a few days as Reiner was allowed to make script, cast, and crew changes before filming eventually resumed. As a result of this, original cast members Charlie Hunnam, Lesley Ann Warren, Tony Bill, and Greta Scacchi were all let go from the project.
In the beginning of the film, on the plane, Jennifer Aniston's character says she's not wearing her engagement ring so she doesn't "steal my sisters thunder". On Friends (1994), Rachel stole Monica's thunder on her engagement night, by kissing Ross.
With only a thirty-five-year age difference between them, Shirley MacLaine was really too young to be playing the grandmother of Jennifer Aniston. Unless you do the math. If Shirley gave birth at the age of seventeen, and her child fathered or gave birth to Jennifer at the age of eighteen, then MacLaine isn't too young.