VanderWaal is also the first female act to win AHS since Bianca Ryan, then age 11, back in AGT Season 1 in 2006.

Nick Cannon and his questionable turban choice told the audience the votes were extremely tight, down to 1 percent difference between the group of finalists. In the end, VanderWaal beat out The Clairvoyants (despite The Clairvoyants having the more Vegas-friendly show, but don't worry, they will be part of her Vegas run -- see below).

After her win, the suitably thrilled young star told People she wants to give a lot of her prize money to charity, probably a music charity, then added this adorable note: "but I want to go on 'Treehouse Masters' and I want to get a treehouse."

Sold! Can't you just picture her up in a treehouse, singing and playing her ukulele? She's a little character.

Simon Cowell told People her win reminded him of another young superstar from his past, a certain "American Idol" OG: "That moment at the end, it reminded me of the Kelly Clarkson moment. You know, when they said, 'And the winner is Kelly Clarkson,' " Cowell told People. "I kind of had that same feeling again when they read her name out, and I saw her reaction and she was literally in pieces. I like that though."

Yeah, we like it, too. Congrats, Grace!

FYI, NBC released details on the Vegas shows, and AGT Season 12:

VanderWaal will headline inside the PH Showroom at Planet Hollywood Resort & Casino in Las Vegas on October 27-29. She will be joined by The Clairvoyants and Tape Face as well. Ticket information can be found at AGTvegas.com or by phone at (702) 777-2782 or (855) 234-7469.

Auditions for season 12 of "America's Got Talent" will kick off in Chicago on Nov. 12 and will make 10 stops throughout the country, including Austin, Texas; Cleveland, Ohio; Jacksonville, Fla.; Philadelphia, Penn.; Las Vegas, Nev.; Charleston, S.C.; Memphis, Tenn.; Los Angeles, Calif.; and New York. For full details or to submit an online audition, please visit www.AGTAuditions.com.

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