The 10 year old male gorilla in the movie who plays Sidney is Kwan. He still lives at Lincoln Park Zoo in Chicago. Kwan is now a silverback over 30 years old and has fathered six offspring. He is a fantastic father and is loved by all. As of the Spring of 2022, Kwan is 33 years-old.
Bonnie Hunt's brother is a physician at Michael Reese Hospital in Chicago. He arranged for the hospital to be used as a setting in the film.
O'Reilly's Restaurant, where so much of the central action takes place, is actually a Chicago landmark eatery known as the "Twin Anchors".
Bill Bartelt: the renowned Chicago water colorist who provided the paintings for Minnie Driver's character, can be seen in the film briefly as an uncredited street artist.