A Simpsons executive producer recently spotted a massive blunder from a 1995 episode

ET Canada

Executive producer Matt Selman noticed that Season 5's “And Maggie Makes Three” episode features a picture of Maggie on the wall in the background while depicting Marge pregnant with Maggie in the foreground. "Oooops," tweeted The Simpsons star Yeardley Smith, while showrunner Al Jean joked that 17 people were fired for the error.