By Mandi Bierly
June 01, 2011 at 04:10 PM EDT

Jimmy Fallon made his first appearance on The Daily Show with Jon Stewart last night to promote his writing staff’s new book Thank You Notes, and like a big brother, Stewart mixed in a few slaps with every pat on the back. (“This [book] had to have been done at least by an intern with tape,” Stewart cracked. He also teased, “Get it now before it blows away.”)

The former SNL “Weekend Update” host  tried to play the admiring little brother, but Stewart was having none of it. He just wanted to talk about how much fun Jimmy seems to be having on his NBC show, which made me wonder if Stewart misses the days when he didn’t have the weight of the nation’s rational thinkers on his shoulders. He shared with the audience the message he left on Fallon’s phone after his “Whip My Hair” duet with Bruce Springsteen (“[Bleep] you”), and the words he spoke to Jimmy when he first got the Late Night gig (“Don’t think you can come after me, kid”). Watch the interview below: 

Later, Fallon later joked that it’s his BFF Stephen Colbert playing the music that accompanies his Thank You Notes bit. “That’s nice. He used to play that music for me,” Stewart said, fake sobbing. (I love how when Jimmy read his sample note, you could tell that Jon was laughing because his arm, the only thing in frame, was moving.)

As someone who’s old enough to have younger colleagues whose energy and creativity I envy, I respect Stewart for handling it the way I do: Encourage and applaud them, while swearing.

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