For some inexplicable reason, the internet randomly decided that yesterday (or today, depending on who you ask) would be Bart Simpsons’s 32nd birthday, if he were capable of aging and also not a made-up character.
As far as I can tell from Google’s incredibly imprecise realtime search, the news of Bart’s mortality appears to have originated from the Twitter account of record label Moodgadget, which got more than a hundred “retweets.” Soon, “Bart Simpson” became a “Trending Topic” on Twitter for quite a while and news of his birthday spread like a funny cat video through Facebook and the rest of the internet.
The date isn’t based on any premiere date (as every Simpsons fan knows, The Simpsons first appeared on The Tracey Ullman Show on April 19, 1987; the Christmas special aired on December 17, 1989; and the series proper premiered on January 14, 1990), any explicit date given in the series, nor the birthdates of his voice actress, Nancy Cartwright (October 25th), or would-be namesake, creator Matt Groening (February 15th).
So, when is Bart’s birthday? The good people over at the Simpsons Archive already determined it years ago. According to the 1992 episode “Lisa’s First Word,” Lisa was born during the 1984 Summer Olympics. Specifically, Marge started going into labor during the women’s 100 meter butterfly, which was scheduled on August 2nd. In the 1997 episode “My Sister, My Sitter,” Bart exclaims that he is “two years and thirty-eight days” older than Lisa, which would put Bart’s birthday on or around June 25th.