Heirloom Design Meets Modern Living: Our Conversation with Petite Keep’s Lindsay Mullenger
There’s something magical about the objects we hold onto—the baby blanket tucked away, the stack of handwritten notes, that something special passed down through generations. Petite Keep, founded by Lindsay Mullenger and featured on Shark Tank, elevates those keepsakes into heirloom-worthy Trunks that feel as beautiful as the memories inside. Thoughtfully crafted and endlessly customizable, these pieces are designed to be treasured now and for decades to come. We sat down with Lindsay to talk about the art of preservation, the inspiration behind Petite Keep, and how design can make even the most sentimental traditions feel fresh and modern.
Tell us about yourself.
Hi! I’m Lindsay—Founder and CEO of Petite Keep, wife, and mom of five. Petite Keep started in my Saint Louis home when I couldn’t find a beautiful place to store my first daughter’s keepsakes as I moved her nursery. Five years later, I’m still pinching myself— the ultimate privilege to build this brand while raising my family, alongside an incredible all-female team. Our Trunks have become part of life’s biggest milestones—welcoming babies, saying “I do,” graduating college—and it’s an honor we’ll never take lightly.
What was the moment or feeling that sparked the idea of Petite Keep?
I searched high and low for a keepsake box to tuck away Heidi’s keepsakes as I organized her nursery in anticipation of her sister Bella’s arrival. I wanted something timeless—worthy of being passed down for generations—with a personal nod to the story it held. I came up empty-handed… and with an entrepreneurial itch, Petite Keep was born.
Did you have a specific keepsake in mind when the inspiration struck?
Key pieces from Heidi’s first year—a birth announcement, her tiny hospital hat, little mementos that marked the year we grew together. I was a first-time mom, and I knew I wanted to keep them close by, yet organized for the future.
You built the business alongside juggling a corporate career and raising a family. How did you manage that transition?
The juggle was possible thanks to a perfect combination: the incredible village that surrounds me, an undeniable passion and belief in what Petite Keep could become, and the unique moment in time that Covid created. With social events and outside commitments on pause, there was a rare focus and quiet that allowed me to pour all of my energy into PK’s early days.
With five children and a husband who was deployed, how do personal milestones and family traditions shape the keepsakes in your own Trunks?
Our Trunks tell the story of our family—first ballet slippers, birthday crowns worn year after year, our wedding invitation suite, and love notes from years of long-distance dating. For me, it’s an opportunity to curate with intention—to hold tight the pieces that have truly shaped us. Over time, those milestones and traditions become more than memories; they become the threads that weave our family’s story together.
Who do you envision when designing for Petite Keep?
When I’m designing for Petite Keep, I picture the exact moment someone opens it—whether it’s a mom tucking away her baby’s first shoes, a bride saving the note her dad slipped her before walking down the aisle, or a grandmother passing along her legacy. I want it to feel personal, timeless, and just a little bit magical—like it was made for their story and no one else’s.
What does the process look like behind the scenes—from the moment someone places an order to when their Trunk arrives at their doorstep?
From the moment your order hits our system, it’s personal! We often huddle around the screen to see the name, monogram, or sweet saying you’ve chosen—it never gets old! Every PK Trunk is hand-assembled right here at the PK Palace in Saint Louis, MO; personalized just for you. Before it heads out the door, it’s inspected and packed so the unboxing feels every bit as special as what’s inside. By the time it reaches your doorstep, it’s been touched by many hands, plenty of smiles, and a whole lot of heart!!
What role does customization play in creating an emotional connection with your customer?
Customization is what transforms a PK Trunk from something beautiful into something theirs. No two are alike—each one is designed with intention, whether by a mom, a bride, or a thoughtful gift giver. That personal touch comes full circle: from the moment it’s envisioned, to the joy of opening it for the first time, to the years ahead when it’s pulled out and the memories come rushing back. Over time, it stops just holding keepsakes—it becomes a keepsake itself, a living piece of someone’s story.
How do you think the act of preserving memories—especially in something so beautifully designed—impacts the way we experience and share our family stories?
I’ve always believed that the way we store our memories shapes the way we share them. When something is kept in a piece that’s as beautiful as the memory itself, you’re more likely to bring it out, tell the story, and pass it along. It’s not tucked away and forgotten—it’s woven into your everyday life. And somewhere along the way, your Trunk stops simply just holding your family’s story…it becomes part of it.
Has there been a particularly meaningful or surprising way a customer has personalized their Petite Keep Trunk that stuck with you?
Honestly? All of them. Every single day at the PK Palace, my team catches me with my jaw on the ground over a new way someone has personalized their Trunk. We’ve seen everything from inside jokes between sisters to a grandmother’s sweet sentiment to a family motto that’s been passed down for generations. No two are ever alike, and that’s what makes it so special—each one feels like it couldn’t belong to anyone else.
You were featured on Shark Tank, which is such an exciting milestone. What was that experience like—both personally and professionally—and how has it influenced the growth of Petite Keep since then?
Shark Tank was one of those pinch-me moments. Personally, it felt surreal to walk down that hallway knowing I was about to tell our attic-to-now story on national TV. What you didn’t see on camera? The hours of practicing my pitch, the pep talks from my team over text, and the electric energy of watching the Sharks interact with our Trunks up close. Professionally, it was transformative for PK—the exposure introduced us to thousands of new customers, validated what we’re building, and opened the door to partnerships that are still shaping our growth today.
What do you see for Petite Keep in the future—any new products, colorways, etc.?
Of course! We listen closely to our customers—the heartbeat of our brand—and design with them in mind. We’re always dreaming up new ways to make Petite Keep even more personal, from fresh colorways and PK Signature Prints to the keepsakes themselves that belong inside the Trunk. The goal is always the same: to create pieces that feel timeless, meaningful, and worthy of the moments they hold.
Take Ten: My Favorite…
Food: Salad and fries, please!
Drink: Iced Coffee
Film: Anything my husband chooses!
Hotel: Four Seasons Maui and Rosewood Mayakoba are two that have captivated my heart!!
City: Stockholm
Tea or Coffee (and how you take it): Any iced coffee, as long as it’s black and bold!!
Playlist: Admittedly, I don’t have anything to put here! My car playlist is on a constant repeat of Daniel Tiger, Kidz Bop, and Disney Princess - mom life! If I have audio moments to myself, it’s almost always a podcast for me!
Weekend Activity: Anything that involves my family - usually some mix of sports sidelines, pancake breakfasts, and dance parties in the kitchen.
Design Book: My SIL (hi, Julia!) has the best taste in design books—so whatever she’s most recently gifted me is always my current favorite.