Not many people know that Will Smith and Jimmy Fallon's grandfathers were an NBC radio show duo back in the 1920s. In fact, they recorded their show in the very same studio where "Late Night With Jimmy Fallon" tapes today. What are the odds?

Even more curious, a lot of their old songs sound eerily familiar to Will Smith's later hits. Not that Jimmy is accusing Will of ripping off his late grandfather... not at all.

Take a look at Smith and Fallon's super old school clip above, and marvel at the off-screen endurance it took to pull this off.

Also on HuffPost:

Loading Slideshow...
  • "Slow Jam The News" With President Obama

  • Bob Dylan Sings the "Charles in Charge" Theme Song

  • Neil Young Sings the "Fresh Prince" Theme Song

  • Pearl Jam Sings "Jeremy (Lin)"

  • "Balls In Your Mouth"

  • Justin Bieber Sings "(It's Not My) Baby"

  • David Bowie Sings "Tebowie"

  • "Tebowie" Part Two

  • The Doors Sing "Reading Rainbow"

  • Neil Young Sings "Pants on the Ground"

  • "History Of Rap" Part Two With Justin Timberlake

  • "Walk Of Shame" With Dave Matthews

  • "Friday" with Stephen Colbert & Taylor Hicks

  • Neil Young & Bruce Springsteen Sing 'Whip My Hair'