Everyone knows that Jimmy Fallon and Justin Timberlake are total BFFs. But they're now BFFs and both dads, which means they're going to be schmoopy together about their kids.

On Wednesday's (Sept. 9) "Tonight Show," Fallon opens Timberlake's interview segment by saying, "We're dads now ... it's the greatest thing in the world, right?"

To which JT replies, "IIt is the most insanely amazing, most beautiful, unbelievable thing that can ever happen to you."

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He also brought along a few pictures of baby Silas, who just turned five months old. He's completely adorable, naturally -- between Timberlake and wife Jessica Biel, that kid is working from a pretty solid gene pool.

Justin also reveals that thanks to Jimmy Fallon's children's book "Your Baby's First Word Will Be Dada," little Silas' first word was, in fact, "dada."

Posted by:Andrea Reiher

TV critic by way of law school, Andrea Reiher enjoys everything from highbrow drama to clever comedy to the best reality TV has to offer. Her TV heroes include CJ Cregg, Spencer Hastings, Diane Lockhart, Juliet O'Hara and Buffy Summers. TV words to live by: "I'm a slayer, ask me how."