The Sister-in-Law Index: What Gen Z Really Wants Right Now

Every time I sit down with brand founders, I talk about CAC, LTV, and media mix modeling.
But in the back of my mind, I’m also asking:
“Would Milana or Mara buy this?”

They’re my 17 and 18-year-old sisters-in-law.
They live in South Florida.
They spend enough on online shopping to prop up a small country’s GDP — and enough time on social to reverse-engineer TikTok’s algo.

So, I decided to make their perspective official.
Introducing the Sister-in-Law Index Report — a running series where I ask my Gen Z focus group what’s working, what’s flopping, and what brands should be doing if they want a shot at relevance.

Let’s dive in 👇

Gamified > Cute > Functional

• Labubus? “They’re cute.”

• Sonny Angels? “Cute naked babies.”
  But the real hook: mystery + exclusivity.
  They’re collectibles. You don’t know what version you’re getting. The drops are limited.
  It’s not just a product — it’s a game. And that gamification makes the dopamine hit even better.
  If your product isn’t fun, exclusive, or part of a ritual… good luck.

Shopping Behavior

• TikTok and Instagram are driving most impulse buys — not search.

• For big ticket items ($300+), they’re not buying directly from your site. They go to Revolve, Farfetch, Saks, or Outnet — trusted marketplaces with easier returns and more perceived legitimacy.

• They’ll buy multiple sizes only if your returns are frictionless.

• They don’t read product reviews. They don’t care about site copy. They want to be the first in their circle to have it.

• Anything under $150? No overthinking. Over $150? Now they’re hunting for better pricing, bundles, or alt options.

• And forget typing in a credit card — Apple Pay or Shop Pay only. If checkout isn’t native, the sale’s gone.

Health & Wellness = Essentials, Not Luxuries

• Pilates, overpriced smoothies, skincare, wellness snacks, facials.

• This isn’t discretionary. It’s daily.

• They’re more dialed into body image and routines than most people were at that age.

• “Being healthy and hot” is a lifestyle, not a goal. And they spend like it.

• Brands in this space are winning by becoming part of rituals — not just selling products.

Influencer Collabs > Influencer Ads

• Micro-collabs work when the brand’s already cool.

• But the ultimate trust signal? Big-name creators actually building or deeply partnering with a brand.

• A one-off #ad doesn’t move them. A fully baked Set Active or Ganni-style collab does.

• If an influencer with 1M+ followers is part of a launch, it's instantly more credible — and more shoppable.
  They don’t want ads. They want insiders.

Purchase Triggers

1. Price: If it’s under $150, it’s impulse territory. If it’s over $150, the education phase begins.

2. Aesthetic: Pink. Maximalist. Limited. Anything boring or overly commercial is ignored.

3. Fit: XXS sizing has to be actual XXS — not vanity marketing.
   (They won’t shop with brands that fake size inclusivity. Edikted? Never again.)

Gen Z shopping habits are often memed — but there’s structure to the chaos.
If you run a DTC brand trying to stay relevant with this demo, start here.

Want the full index, or have something you want me to ask them next time?
Hit reply and let’s talk.