Shot in 22 days.
Ed and Lorraine Warren also investigated the Amityville house and the Perron's house from the "Conjuring".
Early in the film the kids are watching Lost in Space on television. Presumably due to copywriters issues, the vocals of the episode have been dubbed with sound alike voice artists.
Around the 30 min mark when the couple is in bed and hears a voice from the pillow, the voice says, "I don't want Chris to see this". This is a direct quote from The Exorcist when the flashlight is pointed at Regan's belly and the words "help me" become present.