I don’t expect to get one definite answer here, but Google can’t give me one either. Some websites say they’re your second cousin, and others say they’re your first cousin once removed. I’m trying to figure out some family tree stuff so I need to know the difference between the (groups of) terms.
The only story telling I’ve heard it used was A Series of Unfortunate Events. Pretty sure each caretaker gets a cousin designation. But that, of course, is entirely fiction in an excessively diverse, rich, bodacious literary presentation filled to the brim with grimly austere vernacular from the Vocabulary For Defiants.
With such sharp, acidic wit, you might say the prose is… Lemony.