(Illustration by Maggie Chiang/For The Washington Post)

When I was 17 years old, I lied to my mother. I told her that I was sleeping over at my friend Kristof’s house when, in fact, Kristof and I slept in the street, in my mom’s car, so that we could attend a midnight performance of the most outre punk-rock band to play our town in 1982. Wendy O. Williams and the Plasmatics routinely dynamited televisions to smithereens onstage. The singer, Wendy O., sported a blue mohawk and often greeted audiences wearing a dollop of shaving cream around her scrawny midriff.

I can still remember the metallic taste that sat on my tongue as particles of television filtered down to the mosh pit. We were so impressionable then, and also so stupid. Kristof’s mother and mine were friends. They talked. They discovered our lie, and then Kristof was summarily grounded.

My mother’s response was more sanguine, and by the time I was 20 my Plasmatics caper had become, for my mom, a hilarious tale — a story she told to convey how sporting her son was, and how much she loved me despite my idiosyncrasies. She took special delight in the screaming fraudulence of the fake ID that I’d used to gain entry into the 18-and-over gig. (Bought via mail order for $3.50, it bore a generic all-caps header: “STUDENT IDENTIFICATION.”) I was so happy to have escaped punishment. I felt lucky.

And it’s only now, a few months after my mom’s death, that I realize that my good fortune was deeper than luck. My mom had an approach to parenting, a philosophy. She saw raising kids as a happy endeavor, more adventure than science, and she aimed to show me and my two siblings that the world was an amiable place — that you could wander around in it and see interesting things, and then come home and sleep in your own bed, unscathed. Our task as her children was not to obey, but to blossom into the particularized individuals we were meant to be. She wanted surprises. In 1994, when I became a parent myself, she offered me an observation instead of advice: “You expect your children to become clones of yourself,” she wrote in a letter, summing up her own parental journey, “but they don’t, and for that you are secretly glad.”

My mother, Barbara Donahue, was a writer of history books, and she was glad when I followed her lead and became a writer myself — a writer whose method was born, arguably, the night I saw the Plasmatics. Over the past 30 years, I’ve made my living going on gritty adventures. As a freelance journalist, I’ve sneaked into an abandoned beach house that once belonged to Panamanian dictator Manuel Noriega and ridden ATVs with criminals through the strip-mined hills of West Virginia.

In recent years — as my mother crept into her mid-80s, becoming first a widow, then a victim of Parkinson’s disease, then a quavering, cognitively challenged resident of a nursing home — her embrace of my vagabond existence only deepened. I embodied the freedom she’d once felt herself, before she got sick. I was a welcome X factor, arriving, always, with bushels of dirty laundry. (I live in an old house, sans modern appliances.) One night, after she went to sleep and the halls of the nursing home were, at 10, stone-silent and empty, I sprinted to the laundry room naked, so I could wash every stitch I had with me. I told my mom the next morning, and she dined on the tale for weeks. “Wear clothes, Bill,” she began advising me, smirking, her voice reduced to a whisper. “All I ask is that you wear clothes.”

The author, Bill Donahue, and his mother, Barbara, on a trip through New Hampshire in 2014. (Courtesy of Bill Donahue)

The author and his mother, Barbara, in early 1965 outside the family’s home. (Courtesy of Bill Donahue)

We had fun together. Still, Parkinson’s took its toll. The disease ravages every patient differently, its assault on the human nervous system haywire and impossible to predict. My mom’s blood pressure soared and plunged; she fainted often and fell and broke bones and got rushed to the hospital. Some days she could not swallow. We were in a dry land close to death but removed from its mercy. I could not watch, but I watched.

Meanwhile I was faced with a housing problem: As my mom was essentially in a hospital room, I had nowhere to stay when I visited. There were guest rooms at the nursing home, but they felt antiseptic — institutional and cold. There were hotels nearby, but the freelance writer in me was too parsimonious to shell out for a room I’d spend only six hours in, sleeping.

So eventually, in my mom’s final year, I began camping, clandestinely, on the grounds of her retirement home. There was a patch of forest, a grove of pines and maples and oaks, down a wheelchair-friendly path away from the parking lot, and, nights, I sneaked down there, clutching my sleeping bag, my heart pounding as I scanned the darkened horizon for security vehicles. All told, I spent about 15 nights in those woods without being caught.

One thing was certain: I was out there, sleeping on the ground, for my mom. I was living fully, as she wanted her children to do, and I was communing with nature — a noble mission in her eyes. My mom was a lifelong hiker and cross-country skier. Her advice to anyone suffering angst was simple: “Just go outside and get some fresh air!” And she knew these woods well. On mornings that she was herself, she and I fled her room and ventured into the forest, my mom leaning on her walker as she rattled over a small wooden bridge that spanned a swamp there. One spring morning we sat in rapt silence for 15 minutes, watching as two mallard ducks, one male, the other female, floated about each other, now locking eyes, now raising their feet to preen their back feathers. When, finally, they floated away, each to a separate sector of the swamp, my mom remarked, “They’re going home to get ready for the prom.”

I wanted to tell her about what I beheld in and near the woods — the blackberries I picked, the deer I saw, and the way mist rose from the snow when it rained. But as Parkinson’s ate away at her brain, a new constraint emerged: A paranoid streak seeped in, so that she was often afraid, without basis, of the nursing staff. She feared that if she did one tiny thing wrong, she would be forbidden to go outside or to eat meals with her friends. I did not want to give her information that might make her fear reprisal.

So the last story, about my stealth camping, was one that my mother never got to wring for a punchline. It remained a secret. It separated us slightly. It separated who she was in her prime from the fragile, debilitated, scared person she had become.

Or so I assumed when my mom died in January, at age 87. After the memorial service and the burial, I began doing some math. My mom, and my mom alone, had read every word that I’d ever published. She had borne witness to my tricks for over 50 years, and she had amassed an infinitude of details on who I was and how I might behave in every scenario.

In the last few months of my mother’s life, what powers of observation did she have left? It was never clear. Her cognitive ability changed hour to hour, based on her mood and her intake of fluids and drugs. But one soggy morning last autumn when I came in from the woods, my clothes still damp, my sweater flecked with bits of bark, she was at ease as I stepped into her room, her face alight with a warm, amused grin.

“So where did you sleep last night?” she said. Then she paused a moment, readying me for the mention of a name that had been out of circulation for decades. “Was it a sleepover at Kristof’s?”

Bill Donahue is a frequent contributor to the magazine. He lives in New Hampshire.

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