Stories from Suspense Magazine #1 Spring 1951
The idea that a newborn, a tiny baby could be an assassin aiming his sights on his own caregivers, aka his parents, is absurd. Yet, that is the premise of “Small Assassin” by Ray Bradbury that was reprinted in the first edition of Suspense Magazine. The story’s first appeared in Dime Mystery (Nov. 1946).
Despite the premise, the story is well-written and has been reprinted in multiple anthologies, including one named for the story. It was adapted for an EC comic book and an episode of The Ray Bradbury Theater television series and even has a page on Wikipedia.
Here’s the opening paragraph:
“Just when the idea occurred to her that she was being murdered she could not tell. There had been little subtle signs, little suspicions for the past month; things as deep as sea tides in her, like looking at a perfectly calm stretch of cerulean water and liking it and wanting to bathe in it, and finding, just as the tide takes your body into it, that monsters dwell just under the surface, things unseen, bloated, many-armed, sharp-fanged, malignant and inescapable.”
Image from the Wikipedia page.