How much are millennials paying to see the Backstreet Boys in Las Vegas? (Photo illustration: Yahoo News; photos: Mike Coppola/Getty Images, Rich Polk/Penske Media via Getty Images, Christopher Polk/Penske Media via Getty Images)If you see a gaggle of girls in Las Vegas dressed in all white right now, it's because they're ready to turn back the clock. Descending in packs of three, four, sometimes 10, they spill into casino lobbies across the famed Strip, accessorizing their '90s-inspired looks with butterfly clips, body glitter and the unmistakable hum of a chorus so inescapable that you know it the moment you hear it. They're in town to see the Backstreet Boys take the stage at the Sphere, and for two hours, millennial women - moms, professionals, lifelong friends - are ready to reclaim and re-create their youth."I want to relive my childhood memories," Lauren, 33, from Grand Rapids, Mich., tells Yahoo, just hours before the boy band took the stage on Aug. 8. "This was the music I grew up on."Lauren traveled to Nevada with her two best friends: Betsy, 33, from Columbus, Ind., and Megan, 32, also from Grand Rapids. I sat next to them at Casa Playa, a Mexican restaurant at the Wynn Las Vegas, one of at least a dozen tables where girlfriends from all walks of life were catching up before making the trek to the venue. There, the Backstreet Boys would be playing the 13th show of a residency that has likely made its way into the social media feeds of anyone who came of age while the band was in maximum rotation on MTV.

AdvertisementAdvertisementAdvertisementAdvertisementFor Lauren and her friends, an evening of joy was priceless. But that doesn't mean revisiting the '90s for a weekend came cheap.

For each of the women, airfare to Las Vegas was around $700, the Wynn stay was roughly $500 a night and their concert ticket cost totaled $1,337. A budget for merch? Unlimited, they said. The splurge was worth it."It took a little convincing," Betsy said of her husband, who stayed home to watch their almost-2-year-old. "He said Vegas was unsafe, and I said, 'It's not unsafe when you go [without me].'" Laughter rippled across the table, one of many echoes in the room of women buzzing for a long-awaited girls' night out.

This trip, like so many others that evening, was about millennials carving out a moment for themselves while embracing fun, friendship and pure nostalgia.

Moms deserve a '90s kid summer, tooA big talking point among parents is the '90s kid summer trend, which is about encouraging children to have carefree days reminiscent of mom and dad's own experiences growing up: less screen time, more real-world fun. In Las Vegas, this applied to the caregivers.

AdvertisementAdvertisementAdvertisementAdvertisementFor the hundreds of millennial moms who flocked to the Sphere, experiencing the summers of their youth again meant slipping into their best white outfits - a nod to the 25th anniversary of the Backstreet Boys' Millennium album - moving the group chat to IRL, and singing and dancing the night away... while leaving their offspring at home.I grew up more of an NSync fan, but even I couldn't resist the allure of a girls' trip with five of my closest friends who I've known for nearly 20 years, including my college roommate. Among the four of us, we left eight kids in the care of their dads.

An advertisement for the "Backstreet Boys: Into The Millennium" concert is displayed on the Sphere (Kevin Carter/Getty Images)Using a getaway card on the Backstreet Boys was a no-regrets move. Not one person in my group, or the 20 people I spoke with after the show, left disappointed. The boy band, which released its first single, "We've Got It Goin' On" in 1995, delivered a high-energy performance and catered exactly to the audience they knew was there to see them. Our experience wasn't unique - it was universal.

Courtney and Meg, best friends since age 8, had been planning this trip since February, when the Backstreet Boys announced their summer residency. Now 36, they hadn't seen each other in nearly two years, with life keeping them busy in Texas and Wisconsin, respectively. Between them, their children range in age from 4 to 12, but for one night, their mom responsibilities were happily checked at the door.

Longtime friends Courtney and Jen at the Sphere to see the Backstreet Boys. (Yahoo News)Leaving their families wasn't cheap or simple, but the pair said the trip, which averaged around $1,500 per person, was worth every penny. "It was the best time of our lives," they tell me in unison.

AdvertisementAdvertisementAdvertisementAdvertisementAs the crowd funneled into the Sphere, it was clear this wasn't just a concert - it was a reunion of both friends and memories. The crowd, a sea of white, stretched across the venue. Heels clacked against polished floors, glitter and sequins caught the lights. Groups chatted animatedly, reminiscing about study abroad adventures, trading parenting war stories or soaking up a rare night of freedom."