All of Brad Dourif's voice-over work for Chucky was recorded in advance so they could match up Chucky's mouth with the words. Because of this, Dourif rarely appeared on set. Instead, recordings of his voice would be played back for Alex Vincent to go by.
In the later seasons of Seinfeld, a copy of Child's Play 2 (1990) is on the shelf in Jerry's apartment where he keeps his VHS movies.
According to 'Don Mancini' on the commentary for the first film on DVD, the reason the rest of the "Child's Play" films are released by Universal instead of MGM/UA, (despite the first film being very successful)was that United Artits was bought out by a company that wanted to abstain to a "Family Friendly" slate of films. So the property was sold gladly to Universal.