Austin's wall-to-wall itinerary leaves little time for more pedestrian teenage pursuits, which seems to suit him fine. He misses seeing his friends in school but says, "What I'm doing now is way cooler. I could care less about prom." He doesn't smoke weed or drink—"I hate the taste of alcohol. It's disgusting"—and as for girls and relationships and sex, that will have to wait, too. Moms, pinch yourselves. "Yeah, I'm a virgin," he says without a trace of embarrassment or calculation. "I think it's important to wait until you find that special person and not have it be just any random girl. I'm here because of God, and He has a plan for me." Is there anyone out there currently who may fit into this plan? "Nah," he demurs, fidgeting with his ball cap and staring down at the carpet. "I'm too busy right now." Earlier, however, he did make a confession of sorts: "I think Kendall Jenner is really cute, though."

• • •

Forty-eight hours later, in the bowels of Houston's Reliant Stadium, Team Austin huddles in a pre-show prayer circle minutes before taking the stage for the biggest concert of their lives. Locked arm-in-arm are Austin's four male dancers, a DJ, a vocal coach and choreographer, a videographer, a couple of childhood friends, assorted management reps, Michele's dad, Michele, and Austin. Rocco Valdes leads the benediction: "This is our first stadium show, one of many to come. Let's go out there and kill it—murder it!" Austin tells everyone to go out there and have a great show. They bow their heads, pray, and end with a chant: "1-2-3 . . . Mahomies for life!!!"

The day began less glamorously. In the morning, Austin met contest winners at a bowling alley as part of a local radio promotion. Later, in a large conference room at the stadium, he performed a short acoustic set for VIP fans, fielded a few questions (Q. "Do you like tall girls?" A. "I like all girls"), and gamely crooned "Happy Birthday" to one lucky, sobbing preteen. After sound check, as Austin thumbs away at a video game, I ask Valdes if the singer is anxious about tonight's performance; this is maybe his 15th show ever, and it's in a megadome. He shakes his head. "The kid doesn't really get nervous," he says.

It turns out that Austin's stage show isn't yet on a par with his social-media skills. The stadium swallows his vocals, and the dated choreography could be lifted from a Vanilla Ice video. But mostly, it's hard to get a sense of who Austin is, or what, if anything, he wants to say or project. You could argue that these are totally reasonable shortcomings in an artist only a year removed from playing birthday parties, but they're ones that his new class of showbiz peers, such as Bieber and Demi Lovato, have never suffered from. "I'm 16," Austin points out, shrugging his shoulders. "I'm still a kid."

The Mahomies truly perk up only when Austin reaches for an acoustic guitar, grabs a stool, and returns to his bedroom roots. Before launching into impressively raw-nerved versions of two of his biggest YouTube hits, Jesse McCartney's "Beautiful Soul" and Mario's "Let Me Love You," Austin offers an understated intro. "You guys may know these," he says modestly. With the very first familiar chord, the young girls in the stadium stand and hug themselves, screaming in full-throated ecstasy whenever their hero's face appears in close-up on the stadium's giant video screens. As the set ends, Austin sits still on the stage, taking a moment to acknowledge the adoration. He gazes out over the thousands of tweens and teens and tells them precisely what they came to hear: "I couldn't do this without you."

• • •

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