There was an ADULT FICTION book (printed prior to 1996) that was a horror book. I remember little about it but here are the spotting parts I remember. A family had moved I think. There car was a volvo. They had to kids. It was based on mother goose nursery rhymes. There was a witch who kidnapped and kill children. It might have been set in Vermont or Connecticut. The man had an affair with the witch who had the ability to make herself change appearances from an old hag to a beautiful young woman. It was not part of a series that I know of. I've been trying to find the name of the book or the author for over ten years. At the time I was reading authors like Ruby Jean Jensen. Thanks!