Day 23 is reserved for creepy, evil, killer children. I mean, children are pretty damn creepy to begin with, if you think about it (you probably shouldn't think about it). But a good example of taking creepy to 11 is the wide-eyed apparition in this trailer for Mario Bava's 1966 horror flick, Kill, Baby, Kill!
A baroness is having the local villagers killed so her dead daughter can have their souls. The obvious answer to the question of "What do you get the young girl who has everything?" The baroness must be stopped or...bad things. Very bad things. Very bad things that have creepy child laughter--the worst kind.
The opening bit about "Shiver and shake, quiver and quake" makes me think if the film was made here in America, somebody would have made a swingin' theme song for the film, a la The Blob.
It's available on DVD from Amazon.