The “Hell Yeahcore” Trend Is Borrowed from Your Older Sister’s Closet

The fashion version of yelling “get out of my room!”

Amanda Ross

Published on December 09, 2025 07:15AM

Lindsay Lohan, Olivia Rodrigo, and Pink — Getty Images / Shutterstock / Byrdie

Key Takeaways

“Older sistercore” or “hell yeahcore” is trending on TikTok, and it perfectly encapsulates Y2K angst.
Icons of the trend include Lindsay Lohan’s Anna in ‘Freaky Friday,’ Fefe Dobson, and Gwen Stefani.
To get in on the trend, you’ll need lots of plaid, some ironic slogan tees, and a pair of classic Converse.

2000s nostalgia is practically an industry unto itself these days, but the sheer volume of all that “remember when” content means every facet of the era is getting its retroactive appreciation. So much of the decade might have felt glitter-soaked and rhinestone-encrusted, but a newly emerging trend is putting a spotlight on an altogether more extreme niche from the time period. Say hello to what TikTok is interchangeably calling both “hell yeahcore” and “older sistercore,” the youthfully defiant and radically exuberant wave that’s equally fun regardless of whether you’re totally new to the vibe or reliving days past.

Fundamentally, hell yeahcore, which really ruled through the late ‘90s until about 2009, is about taking the concept of a good time to the furthest limits possible. The early aughts were nothing if not big and loud. Crashing into a new millennium, everything from television commercials to food menu items was scaled up to extreme proportions, and American youth could not get enough. Rock and its adjacent genres still topped the charts, we saw the birth of the modern superhero movie, and skateboarding became a pop culture mainstay rather than a relatively niche sport. It’s Mountain Dew and X Games, music so loud it sets off car alarms, and treating whatever low-level hangout your friends are doing like you’re filming an MTV reality show sizzle reel. Despite the overt masculine energy of the movement, though, no one did hell yeah core like the era’s It Girls from film, TV, and music—and their influence is still echoing today.

Lindsay Lohan in 'Freaky Friday' — Shutterstock

The Look

If you were there, you already know the period’s top references. Avril Lavigne, Gwen Stefani, Fefe Dobson, Pink, and characters like Lindsay Lohan’s Anna in the 2003 Freaky Friday remake. Sometimes, you’ll see the trend interchangeably referred to as “older sistercore”, further proof of its influence over millennials and some elder Zoomers. It’s easy to see why eldest daughters, often parentalized and overscheduled, would find the irrelevance and playful chaos alluring. Perhaps no one better embodied the bold, bratty attitude like Avril Lavigne, who managed to translate the angrier, more adult sounds of traditional rock into a sound that a much younger and more female audience could appreciate. And she did it all while igniting more than a few decade-defining fashion and beauty trends that seamlessly fused unbothered tomboy and pop princess aesthetics.

The aesthetic hallmark of older sister core is nonchalance. This was an era of cultivated randomness, when the goal of thrifting wasn’t so much to find an actually cool outfit, but rather the most mundane or off-kilter things you could find. Old youth sports t-shirts and jackets given out by defunct companies were gold—pair that with movement-encouraging baggy jeans, a vinyl belt, and chipped nail polish, and you were set. Notably, the vibe borrows heavily from more overt punk influences, making accessories like spiked cuffs and belts, chokers, and excessive eyeliner commonplace.

Fefe Dobson wearing arm warmers — Getty Images

The easiest way to channel the hell yeah core visual, though, is to introduce some stereotypically or traditionally masculine elements as well. There’s Avril’s now-legendary necktie, of course, but men’s cut belts, shoes, t-shirts, jeans, and boxer shorts are all up for grabs.

Avril Lavigne at the 2022 MTv video awards — Getty Images

The Impact

To understand the resurgence of hell yeah core, you just need to know what immediately preceded the original trend. Really, it was sandwiched right in between the self-serious and morose grunge period of the ’90s and a new wave of youthful nihilism following 9/11. Thinking about the past decade or so, doesn’t it make sense that we’re due for a little irreverence? Olivia Rodrigo might be the closest thing to an Avril Lavigne heir, though she’s taking what the “Complicated” singer started and imbuing it with her own distinct flair. Even her style often channels the time period, with her penchant for jelly bracelets and slogan tank tops.

Spiritually, the hell yeah essence is everywhere, too. Rodrigo’s entire Sour album theme, including the irritated don’t-tell-me-what-to-do eye-roll on the cover, perfectly encapsulates the era’s attitude. KATSEYE’s mega-viral “GNARLY” is full of fun, flippant lyrics over distorted guitar and electronic beats, and there’s even tons of 2000s-inspired outfits in the music video. And while her music more closely references the British indie-pop girlies of the the time period, PinkPanthress’ dedication to red plaid deserves a mention.

PinkPanthress wearing plaid pants — Getty images

There’s Billie Eilish’s penchant for oversized fits—critical for this aesthetic—and Charli XCX’s entire Brat era to look to for inspiration as well, and both superstars are lauded for their take-me-or-leave-me approach to creative authenticity. Really, though, to truly embody the aesthetics philosophy, you must simply agree to have the most fun possible at all costs. Hell yeah.