This unnamed screamer GIF (commonly known as simply Family Picture or Scary Family Picture) pretends to be a still picture of a family. There are 4 people in the picture; 3 of them are young girls, and the other an adult woman. Nothing really happens until a few seconds pass; the picture zooms into the girl in the center (the youngest of them all), and her face turns into a hideous monster with sharp teeth and red eyes. Since it's a GIF image, there is no scream.
NOTE: The following GIF contains a screamer!