The Divine Trio Of Two Sisters & A Husband On Vacation

The sun is beaming down on the crystal clear beach of Luquillo in Puerto Rico, just after a light flash of rainfall. There’s a half-finished case of beer beside my family’s towels, and I’m taking in the view. Everything is perfect, aside from the fact that I’m starving, and then my brother-in-law, John, shows up with a brown bag covered in grease. With barely a word, he hands my older sister Amanda a hunk of something wrapped in foil — a fresh empanada from a street vendor. Before I can feel an even brief pang of jealousy, he hands me one too. Score.

This is what it’s like to be a part of the little sister, older sister, and her husband trio on vacation. This particular sibling dynamic, which has inspired several viral TikTok trends, is no joke. As one creator put it in an April 2025 TikTok, it's “the best trio in the world.”

When you’ve known someone you’re not blood-related to long enough, a sense of closeness inevitably develops, even (and especially) if you wouldn’t be friends in any other context. I’d never have met John if he hadn’t married my sister. We have almost nothing in common: He’s the most millennial to have ever millennial-ed; I’m a chronically online Gen Zer. But we still have a great time together when traveling, be it over empanadas or a late-night debrief.

“Whatever happens on a vacation just mirrors what’s already happening back home,” John tells me when I ask him about the phenomenon. When I visit him and Amanda at their house in New Jersey, he makes sure our wine glasses are always full, plays a movie he doesn’t mind us talking over, and puts their baby to bed so we can have one-on-one sister time. Similarly, on trips, he’ll start our bar tab and sometimes turn in before us so we can giggle together before going to sleep.

Like a lot of 16-year-olds in 2012, when I met John, my eyeliner was probably too thick, and my emotional walls were even thicker. We don’t text often aside from my quarterly message asking for the Disney+ password and his annual plea for Christmas gift ideas. (Even now, he’s calling from Amanda’s number, and she’s listening in via speakerphone.) But the proximity of a family vacation makes our dynamic as a trio shine — and we’re not alone.

Younger Siblings Are Gatekeepers

Older sister energy tends to be type-A and high-strung. Younger sisters (hi! It’s me) are often a little more blasé, chill, and type-B. We’re able to run because our sisters have walked before us. They set the framework for how we are parented, but we get to repay them eventually. Typically, a new partner won’t join a trip until after they’ve met the family at home first. That’s when our opinion becomes integral.

“Younger siblings very much act like gatekeepers,” John says. “I think they have a veto over who their older siblings date.” He recalls how hell-bent he was on getting me to like him early on in their relationship, when I was an angsty teen who hated talking to, well, everyone.

Once he got over the hurdle over time and with persistence, our trio’s strength easily emerged. This feeling isn’t unique. Julia, 28, an older sister, remembers how her now-fiancé broke the ice on his first beach vacation with her family. “He came with subs from [a famous deli], and everybody was the happiest I think that I’ve ever seen them,” she says. From that moment on, he fit right in.

The Holy Trinity Of Storytelling

The ultimate litmus test of a sister’s new partner may be how they debrief after a long day on family vacay.

Julia’s sibling trio is proof that time reaps rewards. “When we go to the beach house for a long weekend and everybody goes to bed, [my sister, fiancé, and I] sit out on the porch and are like, ‘Can you believe this? Did you hear what this person said?’” she says. “[Earlier in our relationship], I would have to give a background to everything. But now, he just jumps and he says stuff that he picks up on.”

Sibling trios don’t just reflect on family stories — they eventually create them too.

John fits into our conversations similarly. He thoughtfully listens whenever my sister and I bring up the same topic again and again, and he’s a great buffer when relatives start retelling stories that Amanda and I have heard hundreds of times, too. Once, when John joined a trip to visit our grandparents in Puerto Rico, my parents, aunt, and uncle were yet again reminiscing in the backyard about their high school days. As the island’s coquis serenaded us, instead of my sister and me rolling our eyes at the old stories, we got to appreciate them again as John heard them for the first time.

The Inside Lore Blossoms

Sibling trios don’t just reflect on family stories — they eventually create them too. John’s first family trip with us was to New York City for my sister’s 21st birthday. He accidentally ordered a pink cocktail garnished with an orchid while my sister ordered a Manhattan, and we still roast him for his whimsical taste. Another time, he didn’t reapply any sunscreen during a beach day in Puerto Rico despite our multiple reminders — he got so sunburnt that he stayed in that night, and we never let him forget it.

“What really adds to [these trips] is now we have inside lore. I’m not just your sister’s boyfriend or husband,” John says. He’s one of us.

Mary, 29, says the best roasts come from a place of love. When she went to Italy with her parents, older sister, and brother-in-law, most of the restaurants they visited offered tables for groups of either four or six. “I was painfully single at the time, so every time the hosts would look at our group and say, ‘Oh, party of five? Not six? Not four? My brother-in-law made sure I knew it was my fault we always caused a scene and had to get a chair added to a four-top,” she says. “Our group chat name is now ‘Party of 5.’”

A great trio’s spark not only impacts the family. It’s also a relationship milestone in its own right. “Once your significant other sees you in context with your sibling, that’s your true self,” Amanda says. “Once you can feel authentic in that, that’s when you get to the really good stuff.”

It’s at this point that Amanda and I each get a text from our dad, then a few missed calls from him and our mom, too. Worried, we end our chat and call each of them back. As it turns out, they were trying to pin down a date for an upcoming family trip, and I can’t wait to see what we get into next.