On almost any given day, a parade of tweens and teens can be seen filing its way through the doors of Un Deux Trois, a girls’ clothing shop on Ventura Boulevard in Studio City. Beckoned by racks of party dresses, pouf skirts and an array of accessories ranging from kitten-heeled pumps to belts encrusted with sparkles, these customers come in search of the perfect outfit, whether it’s for a bat mitzvah, prom or black-tie Hollywood soiree. One of the few brick and mortar stores, and labels, catering to girls ages 7 to 16, Un Deux Trois boasts a clientèle rivaling that of Spago or Stage Deli.

Among the store’s most notable shoppers over its 20-plus year history are: Lindsay Lohan, Noah Cyrus, Apple Martin, Ariel Winter and JoJo Siwa. Enter Un Deux Trois, and it’s instantly obvious why the store and its fashion line have succeeded so well in a sea of clothing brands: when it comes to upscale tween and teen fashion, they are pretty much the only game in town.

Founded by husband-and-wife team Beverly and Colin Shorkend, South African immigrants with backgrounds in fashion merchandising who moved to the United States in 1986, the store boasts that everything is custom-made, all of it designed and sewn and crafted in Los Angeles.

“We’ve dressed every single starlet who has come through Hollywood — they have graced the Un Deux Trois dressing rooms,” says Beverly. “My first starlets were Mary-Kate and Ashley Olsen when they used to do their little videos — they were constantly in our dressing rooms trying on clothes at the age of around 6 or 7.

“This was right after ‘Full House.’ They started to develop a sense of style through us.

“Pretty much any young starlet we have dressed, you name them, we’ve dressed them: Bella Thorne, Storm Reid from ‘Euphoria’; Sylvester Stallone’s daughters grew up wearing our stuff; Heidi Klum’s daughter. There’s just too many to name.

“One day, Steven Spielberg was standing at the counter. He’d come in with one of his daughters. And the girl who was working for us had no clue who it was.

“We train our staff to always ask for people’s names and write down their information. And she said, ‘may have your last name?’ And he said, ‘Spielberg.’ And she asked him to spell it.”

One of Un Deux Trois’ most “exciting” moments, notes Beverly: dressing Sasha and Malia Obama for the January 2009 presidential inauguration.

“Both of them wore our dresses, and they were photographed in People magazine,” says Beverly. “That was probably one of our highlights.”

But what sets Un Deux Trois apart is not just its gladrags– “we have a big selection of different shapes and sizes for all different girls,” says Beverly–but its psychological approach to dressing adolescent girls teetering on the precipice of womanhood. 

“I mean, it’s a very difficult age group– it’s difficult for moms, too,” says Beverly. “It’s a really hard age for these girls to be shopping. We don’t want the girls to grow up too fast, and we make very age-appropriate clothing. But sometimes you have to separate the mom and grandma from the kid to try and figure out what they want to wear. Back in South Africa, I did a degree in psychology, which comes in handy. When I first opened the store, I had a couch and the moms would sit on the couch and spill out all their problems. For some reason, everyone is just so comfortable around us. There have just been the most bizarre conversations. Recently, there was a mom who wrote me a note. She asked me for a piece of paper and kind of apologized that her daughter was acting so strange. We’ve had kids storming out of the store crying, Mom storming out of the store and coming back in five minutes later and buying the three dresses they’ve been fighting about. There is just so much drama in the store–it is crazy.”

The Shorkends’ daughter, Cydney Delemo, is now manager and part owner. Either she or one of the Shorkends is always on hand at the shop.

Colin, whom Beverly credits as “their best salesperson, who sometimes sells more than Cydney,” likens the shop atmosphere to something out of an old 1970’s feature film comedy. 

The interesting thing from my perspective is when the dads come into the shop with the girls,” he says. “Sometimes the moms don’t want to shop with their goals, because they feel too much pressure, or there are stressors or conflict between moms and daughters. So when the dads come in, that bond between fathers and their kids is just amazing to see. It becomes more than just shopping–it becomes an outing, an experience between family members.” 

One incontrovertible truth, notes Delemo: “If a mom likes a dress, the daughter will hate it.”

Whether picking an outfit for a film premiere or a cousin’s birthday party, what’s crucial, says Beverly is “that mom and grandma are really happy with the clothes, as well as the little girl.”

“Sometimes the best time is when the kid walks in with the arms folded because she does not want to be there,” she continues.

And then, by the end of the experience, it’s normally mother and daughter walking around holding hands the girl hugging her mom and telling her how much she loves her. When you can see a kid walk out of the dressing room and she starts twirling, we know that’s when we’ve found the dress. We know we have done our job.”

Visit the store at 12417 Ventura Blvd., Studio City, udtfashion.com