Their only known quotes are "But... Uncle... Krabs!" and "Grumble, grumble, grumble..."
All three of them look exactly like their uncle, Mr. Krabs, except they are much younger and smaller, having shorter noses, and not having an undershirt and a belt; instead they wear light-blue shirts and blue shorts.
According to Mr. Krabs, they solve mysteries. Also, they finish each other's sentences.
"Stanley S. SquarePants"
The group is seen when Mr. Krabs talks about how many relatives got passed over for a job at the Krusty Krab. He explains that he turned them down, and he says that they like to solve mysteries. He demands them to solve the mystery of why they didn't get the job, causing them to walk away in annoyance.
"Lame and Fortune"
One of them appears at Mr. Krabs' funeral.
Mr. Krabs says that they love to solve mysteries, meaning they might be detectives. This is most likely a reference to Huey, Dewey, and Louie from DuckTales.
They refer to Mr. Krabs as Uncle Krabs.
This is confusing, as they should call him Uncle Eugene.
Since they are Mr. Krabs' nephews, they are the cousins of Pearl and grandsons of Betsy Krabs but they haven't been seen interacting with either one.
In "Lame and Fortune," one of them is seen sitting beside their grandmother in Mr. Krabs' funeral fanatsy but doesn't interact with her.
Also, Pearl is present but they don't interact with her either.