Ready for a nostalgia bomb? The Full House cast got together over the weekend to celebrate the birthday of Jeff Franklin — the executive producer of the '90s series — and a bunch of them ended up on stage singing the show's theme song. Kimmy Gibbler herself (aka Andrea Barber) posted a video of the sing-along to Instagram, and hearing the old lyrics come out of the cast members' mouths is priceless. You can see Barber, John Stamos, Lori Loughlin, Candace Cameron Bure, and Bob Saget singing their hearts out. No Olsen twins were present, but it's still a treat.