Place it midway through a scene, after the room has gone quiet and before the character reacts. Follow it with a soft gasp or a sudden fail sting for contrast, and keep earlier toy or nursery sounds lower in the mix so this moment stays the focus.
About this sound
This is a short 3.7-second effect of a wooden rocking horse squeaking back and forth in a steady creak. It feels oddly cozy and a little eerie at the same time, like an empty nursery still moving on its own. The clip comes from Mickey's Magical Christmas: Snowed In at the House of Mouse.