Rich St. Pierre was 7 years old when his mother died suddenly. Well-meaning adults would tell him that “she had gone to a better place.” What, he wondered, was better than home, with him and his siblings? As he grew up, he had hardly any memories and only a few photos of his mother. Eventually, she faded away.

More than 30 years later, Rich faced another tragedy: The love of his life, Carolynne, the mother of his son — and the mother of two children from a previous marriage — was diagnosed with a rare, aggressive form of liver cancer. Rich wanted to do everything he could to make sure his son, Elijah, or EJ, as everyone calls him, wouldn’t experience the same kind of loss that he had.

Carolynne, a maternity nurse known for her sharp wit, had undergone exhaustive experimental treatments around New England, desperate to buy more time. When it looked like it was running out, Rich and Carolynne shifted their focus: journaling, writing letters and recording videos for the kids. They also agreed to let two journalists from the local newspaper document the family’s final months with Carolynne.

At the time, I was a 28-year-old photographer working for The Concord Monitor in New Hampshire. I had no real idea how to navigate a story like this. Now I’m 45, and I probably still don’t. But for 17 years I have watched Rich and EJ both as a documentary observer and, later, as a close family friend. Because I’m not the one in front of the camera, it isn’t always apparent to me that I’m aging alongside him, but my growth as an artist has paralleled EJ’s growth as a person. And my relationship with the St. Pierres has taught me nearly everything I know about intimacy and storytelling, living and dying.

When I began photographing the family, EJ was 3 years old. It was the year before his mother died at age 44. He would shush me when I talked over “SpongeBob SquarePants” and hit me when he was angry, which, understandably, was often. I was one more annoying grown-up coming in and out of the house.

A year or two later, when I came back to town for a visit and to see how they were doing, EJ spoke to me in full sentences. He showed me his pet lizard. I swear, it was pure magic.

I watched as EJ, after fumbling a bit as an adolescent, flourished onstage during his eighth-grade performance of “The Lion King.” He played a grown-up Simba, the lion king who has to overcome the death of a parent. It was impossible not to cry.

More than birthdays and graduations, I have photographed the markers of time in Rich and EJ’s lives: fading furniture, residual fingerprints, trees grown and cut down. My goal is to transcend specificity so others can recognize their own experiences in these images. We all have to navigate loss in life; for some, it’s more acute. One photograph, of a light switch in the St. Pierres’ upstairs bedroom, reminds me of my parents’ divorce.

It doesn’t make sense that I get to watch EJ grow up while Carolynne can’t. But I’m continually in awe of that process. He’s a critical thinker with quiet empathy, always in search of what’s right. Rich says that more than anything else, he sees Carolynne’s sweetness in EJ. Most times when I ask EJ, he doesn’t have any firsthand memories of his mother. But he has the journal she kept, and pictures of her are scattered throughout the house. He also tells me he doesn’t remember a time when I haven’t been making photographs of him.

I decided long ago that the concept of family was malleable. It had to be: As a queer teenager growing up in North Carolina, I often felt a sense of alienation and rejection. My friends and I would refer to other gay people as “family.” My spouse was adopted; we decided not to have children. These days there are, thankfully, many different shapes families can take.

But I don’t think anyone has taught me as much about what family means as Rich. “It’s the staying power,” he told me recently. Rich is one of a handful of people I say I love you to when I hang up the phone. He may be a single father now, but during the time I’ve known the St. Pierres, EJ has had more family members than you can imagine. I’m lucky to be one of them.

Preston Gannaway is a Pulitzer Prize-winning photographer and artist based in the San Francisco Bay Area. Her book of photographs of Rich and EJ St. Pierre, “Remember Me,” is forthcoming.

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