Six decades after the age when most people do, I’ve become obsessed with Lego. My gateway drug was a set reminiscent of an ice cream truck. Like many parents, I was trying something new as a way to connect with one of my kids. Unlike many parents, in my case the kid in question was an adult, and I was building a set that he had designed.

My three boys were infatuated with building blocks as children, and my husband would play with them, teaching the concept of a “stable base.” But I was the one alone with the kids day after day, enduring interminable and soul-crushing afternoons on the floor of the playroom. I remember when the boys were about 3, 7 and 8, feeling like it was an eternity until my husband would get home, and I was thinking: “Lego again? Didn’t we just do this yesterday?” Those hours seemed to go on forever, but one day, impossibly, I blinked, and they were suddenly driving, procuring fake IDs and heading off to college.

Of the three, my middle child, Aaron, was the enigmatic one, the one I couldn’t always understand. We moved from Ohio to the Bay Area when Aaron was in fifth grade, and the transition was almost too much for him. He’d always been change-averse; when I rearranged the furniture in our Ohio family room when Aaron was about 6, he was disconsolate, wailing for days like King Lear in the storm: “Why is everything different?”

The move to California caused him terrible angst; like a sad old turtle retreating into his shell, Aaron lived 24/7 in hoodies with the hoods pulled all the way up for almost a year. I look back at family photos from this time and my heart breaks to see his face, often filled with consternation rather than joy.

So how did Aaron find his equilibrium?

First of all, he discovered musical theater. As a teenager, he was in a dozen musicals at our local community theater. He and I saw Broadway shows together whenever we could: “Hamilton,” “Anything Goes,” “Dear Evan Hansen.” To see Aaron discovering joy through musical theater was a delight (and a relief).

Secondly, Aaron continued building with Lego even as other kids his age outgrew it. During middle school, he found a group of similarly infatuated enthusiasts online who shared their original designs with each other. By the time he was in high school, he had discovered the “adult fans of Lego” community, and that was it for him: He’d found his people.

During college, he started accepting commission work (“Can you design and build a life-size Nike Jordan shoe out of Lego?” “Why, yes!” “How about creating a Balrog, the demonic monster from ‘The Lord of the Rings’?” “You betcha!”). After graduating, he continued with larger and better-paying commissions, cobbling together a burgeoning career.

Aaron’s dream, pretty much ever since he developed fine motor skills, was to work for Lego as a designer. But that would also mean moving to Denmark. After college, he’d begun to teach himself Danish — the kid had his eye on the prize — and, a few years after he graduated, he was hired by Lego.

He and his wife now live in Billund, Denmark, 5,368 miles from our home in the Bay Area.

Last fall, through a fluke of timing, Aaron and I got to spend a few special days together in New York, going to Broadway shows and to a bar in Greenwich Village for a big drunken show-tunes singalong. But it was when we went to the Lego store at Rockefeller Center that I felt like I got a glimpse into the center of his soul. We saw sets he’d designed, and he told me about fellow designers when we checked out their sets. This was his place, these were his people, this was his life — or, at least, it was his foundation.

Thinking about it now, I realize the concept of the “stable base” that my husband taught him all those years ago has become a metaphor for Aaron’s life: This world of interlocking bricks is where he feels the most calm, happy and competent. He needs things to make sense in the way Lego makes sense.

As much as those after-school hours all those years ago felt monotonous, I’d love to go back in time to when we all lived under one roof and when I, the boys’ mom, was the big love of their lives, sitting on the floor of that playroom. Not forever, but just for a little while, armed with the insights I have now.

The time has gone too fast. In the meantime, I have a new and profound connection to Aaron, my sometimes-elusive one. When I dump out a bag of the little plastic bricks and start sorting through them, just the mere sound brings me back, to remember and to feel the essence of my son, however far away he might be.

Abby Margolis Newman is a freelance writer in the Bay Area. @newmaniacs