Based off of three brother rats I have !

Like the actual pets, their OCs like to cause trouble and break stuff and scream.
The difference being that the OCs are kids and my rats are 2 years old.

Their characters are kids because I adopted them when they were still young.

My rats are named Duster (brown), Kyle (grey) and Stan (black)
The characters are respectively named Rigby, Kyle and Stephen Jr. Rigby, unlike his pet counterpart, is not related to Kyle and Stephen

-Rigby likes to escape from wherever he is and explore, steal and break things
-Kyle is a troublemaker who would break your legs if you touch his twin brother. Or because he finds this funny
-Stephen is a very shy and scared kid who follows his brother in whatever he's doing, including getting in trouble. Also pretty gay

(Yeah, the twins' winter clothes are a slight callback to the South Park aesthetic, since well, they're named after SP characters)