Rebecca De Mornay had actually been angling for the part of Tinkerbell in Hook (1991). Losing the role to Julia Roberts prompted her to actively seek something a little darker instead, ironically Julia Roberts was nicknamed "Tinkerhell" by the crew during filming of Hook (1991) due to her difficulty in working with.
The scene where Peyton visits Michael's workplace was filmed at Bio Techniques Laboratories in Redmond, Washington and used company employees as extras. The picturesque wooden building, previously the research center for the historic Simpson Timber Company, was demolished 2 years later to make room for the expansion of Microsoft.
In a draft of the script, Emma is the one caught in the greenhouse trap. However, she survives. Peyton actively kills Marlene by sabotaging her car, causing it to blow up when Marlene lights a cigarette.
The musical theme that is featured in the opening credits, that Payton hums when strolling the baby through the park, and that Michael hears on the radio at the climax is "Poor Wandering One", from the W.S. Gilbert and Arthur Sullivan musical "The Pirates of Penzance".
The Gilbert & Sullivan operas both refer to a nanny switching babies. In Pirates of Penzance, the hard-of-hearing nanny accidentally apprentices an orphaned baby as a Pirate instead of a Pilot. In H.M.S. Pinafore, the noble-born Captain and a lowly sailor were switched by a nanny at birth, and when this is revealed, they both switch positions on the ship.
Sir Arthur Sullivan is cited on more occasions throughout the movie. Already mentioned: Peyton humming music of the "Pirates of Penzance" and the music at the title credits is based on the "Pirates of Penzance". But also, Michael and Emma are singing Sullivan's "HMS Pinafore" in the bathroom at the beginning of the movie; the clock radio in the basement plays more music of the "Pirates of Penzance"; in the house, a poster of Sullivan's "HMS Pinafore" can be seen on the wall.
In the Stephen King novel Doctor Sleep, his sequel to The Shining, he writes the line "the hand that rocks the cradle is the hand that rules the world"; Rebecca De Mornay played Wendy in the miniseries version of The Shining (1997).