Horror Short: Monster Squishes Grandparents' Heads Together For Revealing Story to Grandson

by Kevin
(Jersey)

I saw an early 90's horror short on TV and I can't remember the name. It could have been a Tales From The Darkside episode or something similar. It had three stories and this was one of them:

A young boy is staying at his grandparent's home. They reluctantly begin to tell him a story or song about some creature. They say they have to finish it quickly or the monster will arrive and kill them for telling it.

In the end, they don't finish the story and two large monster-looking arms burst through the glass windows and squish the grandparents' heads while they boy sits near a fireplace in horror.

I have searched the web and asked everyone I know with no results. I would appriciate your help.