“Dead mother sitting in a rocking chair”

LORELAI: Let me just say, if we walk in there and his dead mother is sitting in a rocking chair, not a bit surprised.

A reference to the 1960 film Psycho, previously discussed.

In the film, the deranged murderer kills his own mother, but keeps her in the basement sitting in a rocking chair, treating her as if she were still alive. This seems to be another clue that Lorelai suspects Dwight of murdering Beenie Morrison, or being a serial killer.