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Earlier this week, news outlets published the results of a public-records investigation into what caused a massive wildfire in Arizona’s Santa Rita foothills last year. The video footage procured by Arizona Daily Star reporters confirms what those who’d been following the case feared: The blaze began with a giant eruption of blue powder.

A U.S. Border Patrol agent and then-expecting father was attempting to create a spectacle out of the revelation of his baby-to-be’s gender, so he shot a rifle into a target filled with an explosive combination of oxidizers and fuel. As one journalist put it, the plan “was doomed from the start”: The area had been experiencing less-than-average rainfall and unusually high winds. Upon exploding into a plume of cerulean-colored smoke—it was a boy!— the target set off a blaze that ravaged the surrounding mesquite trees and yellow grassland. The man’s gender-reveal party ended up burning 47,000 acres of parched state land, and cost $8.2 million to extinguish.

While this man and other parents-to-be have approached lethal extremes in pursuit of a legendary gender reveal for their unborn baby (see also: the Louisiana couple who recruited a 10-foot alligator named Sally to help them divulge the surprise), most participants in the gender-reveal trend have more manageable celebrations. Take the 20-year-old Juliann Mladineo. Just a few months into her first pregnancy, Mladineo was convinced she was having a girl. She and her 21-year-old boyfriend had initially decided to hold off on learning the baby’s sex until birth, and the mystery made the already special pregnancy process “extremely exciting,” Mladineo says.

But some of their relatives already knew the baby’s sex; her sister had found out early on, when she accompanied Mladineo to the hospital for the gender-revealing ultrasound, and she spilled the beans to a few family members. They kept teasing Mladineo and her boyfriend. Eventually, the couple just couldn’t resist any longer. They gave in to their relatives, and to another pressure as well: the temptation to leverage all the mystery and the surrounding hype and funnel it into a party.

A scene from Mladineo’s gender-reveal party (Christina Hernandez-Mladineo)

Mladineo, who first learned about gender-reveal parties about a year ago, had noticed that many of her San Pedro, California, peers were having them, with a lot of them broadcasting footage of the spectacle on Facebook or Instagram. So when the temptation grew unbearable, Mladineo and her boyfriend decided that they, too, would trade in their thrilling mystery for an opportunity to partake in the fun. They invited around 60 of their friends and family members over to her parents’ backyard. Guests—minus those who already knew—marked their prediction for the baby’s sex on a chalkboard or on Polaroid pictures they’d taken of themselves and hung on a rope, all while snacking on color-coded cupcakes and chocolate cigars.

Mladineo’s family served pink and blue cupcakes at the party. (Christina Hernandez-Mladineo)

At the end, they set off confetti poppers, which, to Mladineo’s surprise, rained down blue scraps of paper onto the guests. In February, Mladineo can expect to give birth to a baby boy. But this isn’t the last time the couple will celebrate the baby—Mladineo plans to have a shower, too.

For American 20- and 30-somethings, who are in the thick of the milestone-heavy phase of early adulthood, it has become common to have multiple celebratory events to honor landmarks such as births and weddings. A busy wedding-season calendar for a young adult in 2018 is often peppered with commitments—not just the weddings themselves, but a marathon of additional parties that sandwich the ceremonies. At its most extreme, that marathon may be an indulgent prix fixe menu whose dishes include, say, a ritzy engagement party, bachelor(ette) weekends in Las Vegas and Nashville, a bridal-party lunch, a rehearsal dinner and pre-wedding bar night, and an after-wedding couple’s shower (in addition, of course, to the wedding and the reception).

Lavish weddings had become trendy in the United States by the 1990s, according to Beth Montemurro, a sociology professor at Penn State University at Abington and the author of the 2006 book Something Old, Something Bold. And this shift instigated a sort of celebratory creep, not only stretching traditional celebrations like weddings and births into multiple events, but inspiring celebrations for life events that historically passed without much fanfare: things like divorces, job departures, pets’ birthdays, and asking someone to prom (now known as a “promposal”).

While data on the popularity of these parties are hard to come by, scholars and industry experts tend to agree that these newfangled celebrations are on the rise. And online, Reddit forums and Pinterest boards offer prospective hosts a seemingly endless array of suggestions for activities and decorations for all manner of celebrations, from postpartum parties to post-wedding showers. Many of these hyper-specific themed decorations can be found on Amazon or at Walmart and Party City, which, due to growing demand, now dedicates eight feet of shelf space to gender-reveal products in its brick-and-mortar stores.

Businesses are seeing a need, and filling it. Take, for example, the story of Dana Lawrence, who a few years ago co-founded an online divorce-party-supply store with her then–newly divorced sister. Sometimes a separation merits just as much celebration as a union, they’d agreed, yet the internet was devoid of ideas or supplies for such parties. Today divorcés can turn to the sisters’ store, The Unknotted, for their party needs, including Ex-Wifey T-shirts, Unbridled sashes, and I Don’t cake toppers.

All in all, these trends signal a push toward “public celebrations of things that used to be more privately or intimately celebrated,” says Carly Gieseler, a professor of communications at the City University of New York who authored a 2017 study examining the social forces behind and impacts of gender-reveal parties. Echoing other industry observers, Gieseler concluded that gender-reveal parties have surged in popularity since the late 2000s, when, her analysis found, the first video of a gender-reveal party was posted on YouTube. Since then, these events have gotten just more and more over the top.

The biggest factor, according to Gieseler’s analysis, is social media. It’s on these platforms that expecting parents “not only offer ideas but market products to achieve the ideal image of the celebration,” Gieseler writes—ideas and marketing that, in turn, proliferate across those same virtual networks, “giving legs to the trend and gaining advertising capital as sources.”

BabyCenter’s most recent annual trends report found that 40 percent of the moms-to-be surveyed by the advice website had a gender-reveal party or announcement this year, a figure up 30 percent from that in 2017 and nearly double that in 2016, according to the website’s spokeswoman.

On the one hand, the publicizing of private moments could be a way of making the event feel more special, or of celebrating those moments with more loved ones than might otherwise be possible with a stand-alone party. On the other, this impulse is expensive, creating tension for guests who feel weary from expanding obligations and the ambiguity surrounding gift-giving conventions.

Lizzie Post of the Emily Post Institute, the self-proclaimed etiquette “authority” that for decades has “maintained” and “evolved” the decorum governing American society, stresses that nontraditional events such as gender-reveal parties by definition are not a “have-to” and thus don’t come with a set etiquette. But it’s hard to avoid the pressure when these once unconventional parties start to feel, well, conventional. “The more you add these [parties] in until they become institutionalized, the more it creates this anxiety about what’s right and how much celebrating there should be for these events,” Montemurro says.

Complicating this tendency toward over-celebration is globalization. Many loved ones are living farther apart than ever and multicultural families have become more common. Extra parties can serve as a way for the hosts to celebrate with folks who live far away and either can’t attend the main event or have to travel long distances to do so, says Catherine Clark, a senior editor at Offbeat Bride, a website that publishes unconventional wedding advice for women. “You end up with these far-flung guests who need to be entertained for longer during the weekend or, if it’s hard for them to attend the main event, with these ‘satellite’ celebrations in which you travel to them or they come to you,” Clark says. Having multiple celebrations for a wedding is also a way to incorporate different cultural traditions.

New traditions can also address a growing desire among couples to have co-ed life-event celebrations; a post-wedding couple’s shower, for example, can supplement pre-wedding gender-segregated bachelor and bachelorette parties. And as Americans are marrying and having kids later in life, many of them are more independent by the time these milestones come around—financially and otherwise. They may feel less beholden to the desires of their more traditional relatives. For example, perhaps a couple will choose to have a very small wedding and tack on a post-wedding reception open to an extended list of loved ones.

That was the logic of Allison Fitzpatrick and her husband, who got married this past April in an intimate ceremony attended by only a handful of immediate family members. The couple, both in their mid-30s, decided to have a post-wedding reception in June in an effort to celebrate with roughly 50 extended family members and friends without the pressure attached to a traditional wedding. “There’s definitely a lot of pressure in the wedding community to have a unique reception, to personalize everything,” says Fitzpatrick, who lives in Charlotte, North Carolina. “When it came to my reception, I was honestly just like, ‘I want to eat good food, hang out with my friends, have good drinks’—I don’t want to be worrying about whether my floral arrangement was exactly right or that kind of thing.” She describes her post-wedding party as a “family reunion meets celebration.”

But still: One of the biggest—if not the biggest—factors driving this phenomenon is social media. These parties wouldn’t be so popular if it weren’t for the exposure they get on platforms like Facebook and Instagram, where others see them and, perhaps, then feel inclined to throw their own. Social media can amplify forces such as ego, peer pressure, and FOMO. Perhaps America’s young adults are celebrating so much because they’re accustomed to packaging the events of their life into narratives for their virtual networks. “Social media has unleashed an era of disclosure and access transforming the intimate phases of pregnancy into public knowledge; the gender-reveal marks one of the more pivotal points in this public process,” Gieseler wrote in her 2017 study.

The visibility of such parties online can also make the celebration of life events seem like a game, “in terms of who’s going to win the most social-media currency, who’s going to gain all the ‘likes,’ the views, the video-sharing numbers,” Gieseler told me. There’s a consumerist element to these parties, not just in how they are broadcast to be consumed online, but in the expense they create for both hosts and guests. While presents might not be expected at gender reveals or pet birthday parties, attendees might bring them anyway to avoid showing up empty-handed. Destination bachelorette parties and wedding showers can feel like obligatory, unreasonable additional expenditures for guests. “Now that we’re starting to spread those things through social media, it really becomes this consumerist phenomenon,” Gieseler says.

Social media may also be fueling this trend in a subtler, more roundabout way. When so much socializing happens online, it may be that any excuse to gather loved ones under a single roof is more appealing than ever. And the time of life when these milestones tend to accrete is also a time of great family and work responsibilities, as well as of moving from place to place, and young adults may find themselves with less time for their friends. When your peers’ free time seems ever-shrinking, inviting friends over to hang out just because can feel like an imposition.

But asking everyone to get together might feel easier if you have a reason: a new child, a marriage, even a divorce. “When there’s an excuse to get everyone together, then you kind of have to jump on it,” says Clark, of Offbeat Bride. “Otherwise, you’re just scrolling, looking at everyone’s baby pictures from your living room, and that can get very sad.”

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