Fred Rogers died in February 2003, meaning there are nearly nine years' worth of kids who've been born into and grown up in a world without Mister Rogers.
Don't dwell on it, though -- Rogers wouldn't want you to. Instead, remember the good times with this compilation of Rogers singing his show's iconic theme song, which he did almost 900 times over the 30+ years that 'Mister Rogers' Neighborhood' was on the air. Best. Neighbor. Ever.