Drew Barrymore  and Adam Sandler  appeared on The Tonight Show Starring Jimmy Fallon  to promote their upcoming comedy, Blended, and gave the audience a sweet treat. The pair, who first appeared together in 1998's The Wedding Singer, then again in 2004 for 50 First Dates, sang the "Every 10 Years" song about their romantic reunions — with a little help from Fallon on the guitar. Did you know Barrymore is the Rob Ford to Sandler's crack cocaine? As funny as the lyrics were, the best part comes at the end, when Sandler unexpectedly sings a bit of "Grow Old With You," the song he sings to her at the end of The Wedding Singer. Also worth the watch: Barrymore's reaction when Sandler asks if he's a better leading man than Fallon, who starred opposite Barrymore in Fever Pitch.