system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: It is said that children are (almost) immune to motion sickness up to the age of 2. Why?
gpt
The main reason for motion sickness is our body has trouble reconciling the visual cues for no movement with the physical sensation of movement.  The difference causes our bod to freak out, and we throw up to expel whatever apparent poison we've consumed.

Children don't have the history to realize there is a discrepancy yet.