Shot in seven weeks.
Leonard Maltin gave this a decent enough review (for a horror movie, which he usually slams). He said it "builds up to, and then backs away from, the lesbian and incestuous implications of its premise.". Maltin has a point, the movie may have been more shocking and devasting if it went full throttle in this direction, much like Paul Schrader's Cat People, or Edgar Allen Poe's Fall of the House of Usher, showing a shocking incest attack, stalking and then revenge, showing how this dynamic has a horrific effect on the family.
Jack is about to board an aircraft, a British HS-125. The registration, seen under the wing, is CF-SIM. However Canadian registration prefixes switched from 'CF' to 'C' starting in 1974. By 1988 it would be unlikely for this aircraft still to be carrying a CF style registration. It should be C-FSIM by 1988. Presumably the aircraft had been sitting around out of use and thus for change to it's apparent registration.