<em>The Simpsons,</em> an animated sitcom about a working-class family of parents and their three kids, is the longest-running American sitcom ever, having been on the air for 30 seasons since 1989. Despite how long the series has run – viewers who were 10 when they first started watching would now be pushing 40! - the family never ages. Homer and Marge remain their spritely selves, Bart is always a trouble-making 10-year-old, Lisa a precocious and intelligent eight-year-old, and Maggie a rarely-speaking, pacifier-addicted baby.