Oddly enough, on page 180 of the original hardcover edition of this book, which is a fine book, by the way, there's an error that's hard to miss.
While talking of the heroine's son, Chris, things that scared him were mentioned.
These things include the lightning in Dr Frankenstein's lab in the original movie, lightning that scared Donald Duck, and the stormy night in 101 Dalmations during which Drusilla DeVille threatened the puppies.
Drusilla Deville...what happened to Cruella?? Is Drusilla her evil(er) twin??
Beats me, but there it is...