"I started to explain to her that Karen has some negative connotations and has become a sort of internet joke to describe a very specific kind of entitled middle-aged woman," she added.
According to the cousin, Stephanie reacted terribly to the news and was "furious".
"I wasn't trying to tell Stephanie not to name her daughter Karen, I just wanted her to make an informed decision," she wrote. "I'd want someone to do the same for me."
Over 300 people responded to the thread, with many slamming the cousin for being "insensitive."
"You are definitely the a**hole," wrote one.
"You really think it's still going to matter when this kid grows up? It's a meme."
Some readers, however, agreed that it was a terrible choice.
"To be fair to you, Karen is a pretty crappy name."
Kiwi comedian Tom Sainsbury has also interpreted the classic Karen character as his very own "Cathreen"
