system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Please explain how first, second, third and so on cousins work?

Also what does ‘once and twice removed’ cousins work in that context?
gpt
brother/sister - same parents

1st cousins - share grandparents

2nd cousins - share great grandparents

and so on.

Removed is by generation downwards. The children of your first cousins are your first cousins once removed. The grandchildren of your first cousins are your first cousins twice removed.