Fainting goats
There are videos of baby goats on the internet that faint when you scare them: They have a genetic mutation where fear cuts control of their muscles.
It is funny, as much as it is tragic.
The adult goats learn to not faint. Instead, they freeze and become as stiff as planks. Staying upright, they can hobble-horse along until they gain control again.
It is funny, as much as it is tragic, that we sometimes hobble-horse along in life.
When fear enters the system like that, we lose access to our most precious ability: To play, freely.