Grace and Freddie did their own vocals to scare Lily and Herman

I thought the mean Munsters just used recordings but after watching the movie as an adult I noticed the skull in the painting panel laughing had Grace's voice and the Skeleton in the closet had distinctly Freddie screaming loudly. Interesting discovery but not as good as discovering how beautiful, sexy and appealing Debbie Watson (as Marilyn Munster) is. I have come to watch her in lots of other shows and I love her in everything I see her in.