"The Simpsons" Eye Thing

Simpsons Family Photo

I noticed something while watching The Simpsons. Only the immediate Simpson family (Homer, Marge, Bart, Lisa, Maggie & the Dog) has eyes that are touching, and almost every character on the show has their eyes apart. What's up with that? Is it a status thing? Because the five main character are more important and everyone else is expendable? Take a look...





No examine this picture, aside from the few Homer doubles (and Homer's mother), every character has eyes with a space between them.

The Simpsons Group Portrait

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Any idea why the eyes are done in this way? Is the there a story behind this?

I remember a few years back, during a film documenting "The Simpsons" success around the world, the argument was brought up saying the eyes of Simpsons characters resemble that of a woman's chest, mainly the eyes being likened to breasts. 

Could the eyes of characters on The Simpsons have aided in the success of this television franchise? And if so, was it intentional or just a very fortunate mistake?