system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do your eyelids get puffy after crying?
gpt
There are a number of factors. 

Tears from strong emotions are less salty than regular tears which keep your eyeball moist. Since your eyelids are "more salty" than the tears, the water from your tears goes into your eyelid tissue to balance out the amount of salt, causing the eyelid to swell.

You could also say that blood vessels around the eyelid have to expand in order to be able to deliver that much fluid for waterworks. Also, rubbing your eyes can cause it to swell, as the friction can cause irritation of the membranes around your eyes (conjunctiva).