I don't recall seeing such an adventure (the closest being possible the one with Maligno?), but you might want to get your hands on a used copy of
Little Fears (the role playing game of childhood terrors). See
https://www.funsizedgames.com/little-fears/
Little Fears is a horror RPG. The game has a unique premise: players take on the roles of children, between the ages of 6 and 12. The game is rules-light and quick to learn.
The world of Little Fears is a dark one, where childhood fears are real. Monsters lurk in closets, under beds, and in shadows, preying on children's innocence and imagination.
Since characters are children, combat is rarely a viable option; creativity, courage, and teamwork are key to survival.
The tone can vary from strange and eerie fairy tale horror to unsettling psychological terrors.
---
I have that crazy idea of using it in my campaign someday. The PCs arrive in a town where children disappear.
*switch* The players are handed other character sheets. They have to play the children against the bogeymen à la Dark Tales & disturning legends.
They can’t talk to an adult (or their PCs) – the adults won’t listen, they are too busy, they do not believe the children, etc. The grown-ups won’t listen.
So they really have to play children against monsters!
Their goal is to last long enough, so the adults make their own inquiries against the children disappearing. Example, they have to last a week.
*switch* Time go back a week and the players, with their usual PC sheet, have to investigate the children’s disappearance
---
Example of possible LF adventures:
The Sleepover Gone Wrong – A group of kids at a sleepover realizes that one of their friends has vanished into the closet. Can they bring them back before sunrise?
The Substitute Teacher – A creepy new teacher at school seems too perfect. Rumors say that students who stay after class never come back...
The Slide's Secret - If a kid goes down the slide alone at night, they never come out the other end. Instead, they find themselves in the Playground That Was, an eerie, abandoned version of the park where the swings creak on their own, the seesaws move without anyone on them, and the slide stretches into a tunnel leading to darkness.
Possible Resolutions that can work for children:
The kids can find and free the lost children by solving the Games of the Playground (e.g., a puzzle? a tag match against shadowy figures?).
Destroying the Slide?
---
The tricky part is playing the adult PC after that, there should be a twist I haven’t got yet. Of course the PC can destroy the bogeyman, something the kids can't do.
Or it could be 50 % of players have their usual PC sheets, 50 % of players have kids sheet. They can't talk to each other (the grownup won't listen) for a week, then that frontier is removed. Could work too.