He seemed to be waiting to catch my eye. I gazed absently as he stood there, smiling faintly from the cover of a bright blue book nestled discreetly among other new releases. Across his chest bold letters read, Donal’s Mountain: How One Son Inspired a Nation, while a yellow bracelet hung loosely on his wrist. My focus was about ready to move along the shelf, but it stayed fixed on his wrist. A yellow bracelet. My stomach clenched. Is it LiveStrong? I turned over the book, scanning the synopsis for more clues: Irish teenager…sixteen years old…cancer… died last year. My racing mind lurched to a halt. But what kind of cancer? I tore through the pages, poring over words until it jumped out at me, as if waiting to pounce: osteosarcoma.

My dad walked across the small bookstore and asked what I was reading. I stammered, pointing to the cover: “This Irish kid – he had bone cancer, too.” Intrigued, he took it from my hands and suggested we get it. I protested weakly, feigning indifference. “No, Dad, I already got a book, it’s OK.” I was deeply ambivalent – unsure whether I wanted to take the omen or leave it on the shelf – so I used the James Joyce novel I had just bought as an excuse to deflect the decision back into the universe. He insisted on it and went to the counter to buy it as I stood there staring ahead, no longer at books. He handed the bag to me and I buried it deep in my coat before we pushed our way out into the grey, drizzling rain of the Irish coast.

One last place we wanted to see – an old church we had spotted earlier that morning – stood across the cobbled street. The door was unlocked and we entered, silently tracing the circumference of the empty pews. I stayed a few steps ahead of my dad, not wanting him to see my face. A strange mixture of guilt and gratitude gripped me, pushing a wall of tears to the surface that I strained to keep from blinking away. Who is this kid? Why did he die and why did I live?

In 2014 I had come to Ireland to revel in my hard-won freedom – freedom from a hospital in Boston where a year prior, at the age of twenty-five, I had finished a grueling, nine-month treatment for osteosarcoma, a rare and aggressive bone cancer that had been found in my right femur. Much of the bone in my leg had been replaced by metal, and it was weaker now, but I had regained enough strength to at least carry a backpack and roam far from the confines of a hospital. I was there in Ireland to get lost somewhere in Joyce country, to take time and space to process a year that had left me with, among many things both beautiful and terrible, a deep urge to write. I would spend the summer there on my own, but my dad was joining me for the first week before releasing me into a homeland neither of us had seen before. We had rented a car and were traversing the island, which had led us to a small town at the end of this remote peninsula. It was here, on the third day of our journey, that Donal Walsh found me.

We left the church and I asked my dad to drive; I felt the book burning a hole in my coat pocket. Instead of marveling at the breathtaking scenery – lush green hills rolling into jagged gray rock that splintered into the ocean – my eyes stayed glued to my lap. I tore through the first few chapters, reading about Donal’s childhood and how he had grown up in a small town in County Kerry that was best known for an old white windmill that had stood for over two centuries. I had just read about his initial diagnosis at age twelve when my dad said he was tired and asked if I could drive instead. I was reluctant to stop reading, but agreed. I drove distractedly, my mind still drifting through Donal’s childhood, as I began to pass road signs with names that seemed oddly familiar. Where have I seen these before? Before ten minutes had passed, I spotted, in the distance, the white windmill.

My dad had fallen asleep, but I pulled off the highway and made my way to the landmark. A policeman was standing nearby, and I got out of the car and approached him, stumbling through an introduction before asking about the Walshes. “Oh sure, everybody knows ’em, poor things,” he said. I held my breath. “Their house is the gray one, just over there.” He pointed to a row of houses lining a small canal that stood a stone’s throw away.

I got back in the car and sat for a few long moments, staring out the windshield. My dad had woken up and seemed confused. “They live right there,” I murmured, pointing to the book and then motioning across the car. My dad looked out his window, then back at me, then out the window again. We drove over to the house in silence, and I got out and approached the door. I knocked weakly and waited a long minute, hearing nothing inside. I was about to walk away when a woman answered.

“Hi.” I searched for words. “Are you Elma?”

A certain gravity seemed to be pulling things forward to an uncanny yet somehow unsurprising conclusion. With each step – from the blue book to the white windmill to the grey house – came a growing sense of purpose. It didn’t feel as if I were caught in a trance. Rather, there seemed to be an unspoken invitation to meet each moment with a simple “Yes, this too.” In the Celtic tradition, caol áit, or “thin places,” are locations where the boundary between the physical world and the spiritual world is especially permeable. Had I, within days of arriving in Ireland, stumbled my way into such a place? From within the experience, it felt strangely natural, seamless, effortless. But, looking at it from the outside, it was baffling.

Osteosarcoma, a primary bone cancer mostly affecting teenage boys, is rare by any measure. In the United States, about a thousand people get it each year. In Ireland: a dozen or two. The likelihood of a chance encounter between two families affected by the disease, even those who aren’t separated by an ocean, is staggeringly small. I would later learn that the book, written by Donal’s father, Fionnbar, had been published just a few weeks earlier and may have preceded my arrival to that remote peninsula by only a few days. I had found it while aimlessly browsing in a nondescript bookstore looking for Joyce. And now, less than an hour later, we were seated in Donal’s kitchen, sipping tea with his mother.

Elma and I plied each other with questions, starting from the beginning. Where was the tumor? Which leg? How much metal did they put in? Elma got Donal’s x-rays from a cupboard and I pulled up photos on my phone. We held them side by side: same leg, same cut marks, same metal implant. My dad sat off to the side and watched, quietly drinking his tea and softly cooing “wow” every so often. We talked about the illness – the chemotherapy, the side effects, the drugs to manage side effects – the minutia of cancer treatment that, apart from clinicians, only a patient and his caregiver would know. It struck me that Elma probably had never spoken this cryptic language with anyone but her son, and that I hadn’t with others beyond my own mother. Our conversation was a strange entrance back into a world that we thought we had locked away in the past.

Five years earlier, in 2009, Donal had just completed a nine-month regimen of chemotherapy and surgery – the same one I would later undergo – leaving him cancer-free and ready to barrel ahead into his teenage years. But he didn’t leave it all in the past. His experience in the overcrowded and rundown children’s hospital in Dublin – the only one in Ireland that provided the treatment he needed – motivated him to fundraise for building renovations. Over the next few years, he helped his father coach youth rugby, a sport he had dreamed of playing professionally since he was a child. Now, with a weakened leg, he had to resort to watching his peers from the sidelines, pouring his energy into leading exercises and drills in whatever ways he could. His leadership skills blossomed as he earned the respect of the young players, who saw that his dedication and commitment to the sport rivaled that of anyone on the field.

Then, in early 2012, a routine scan revealed that the cancer had metastasized from his bones to his lungs after lying dormant for nearly three years. Donal and his family were crestfallen but determined to push through the surgery and four months of chemotherapy that he needed to save his life. He tolerated the regimen well, even managing to stay physically active through his treatment. But several months later, another scan revealed that the cancer had come back, this time in his spine. The doctors said that the treatment options had been exhausted. He had survived cancer twice, but this mountain would be too high for him to scale. It was October, and the doctors recommended that he and his family have an early Christmas.

Ireland had been hit especially hard by the global economic recession of 2008, resulting in a scourge of suicides among young people, particularly young men who had lost jobs and were out of work. The national rate had surged, making Ireland’s the one of the highest in Europe. In the last year of his life, Donal personally knew of three young people in the area who had died by suicide. On his own initiative, he wrote a letter about how much it saddened him to see young people losing their lives. He pleaded for people to seek help, to trust that people cared. “So please, as a sixteen-year-old who has no say in his death sentence, who has no choice in the pain he is about to cause [others] and who would take any chance at even a few more months on this planet, appreciate what you have, know that there are always other options and help is always there.” In the face of despair, he insisted on hope. “So I’d say to someone who’s standing there in a room where they feel there’s no windows and no doors, just black, to take time and … a door will open.” Donal had told his parents that he only wanted the letter to be shared after his death, but after he won an award for his fundraising efforts and a local newspaper inquired about any writing he might want to share, he decided to have it published. The letter struck a nerve in the Irish psyche, going viral and being reprinted in newspapers around the country. Days later, he was asked to come on a national evening talk show and speak more about his message. With his health declining, his parents warily agreed.

Elma invited my dad and me into the living room to view a recording of Donal’s interview. As we watched him telling his story – his struggle with cancer, his charity and advocacy work, his message about mental health awareness – I was drawn mostly to his affect, his serene, steady demeanor. His speech was deliberate and not rushed, clipped by audible inhales, a light gulping for breath due to his diminished lung capacity. “If I’m meant to be a symbol for people to appreciate life more” he said, “then I’ll be happy to die, if that’s what I’m dying for.”

Donal didn’t need to have an early Christmas; he outlived his prognosis by more than six months and died on May 12, 2013. An ocean away in Boston, on that very same day, I completed my own cancer treatment. Three days later, on May 15, when Donal was buried at a funeral attended by upward of seven thousand people, I received my post-treatment scans and my medical team officially declared me cancer-free. One year later, almost to the day, I would show up on Donal’s doorstep to meet his mother.

His death sent ripples throughout the country. On Twitter, his followers spiked from a few hundred to twenty-four thousand, and the moniker #LiveLife topped the charts. Thousands of letters and donations started pouring into the Walsh’s mailbox, prompting Elma and Fionnbar to create The Donal Walsh #LiveLife Foundation, which raises awareness for two seemingly disparate causes: pediatric cancer treatment and teen mental health awareness. Six months after Donal’s death, the coroner in County Kerry reported that suicide rates had dropped measurably. With his parting message, Donal had likely saved more than a few lives.

At the end of the summer, before I returned to Boston, I stayed a few days with the Walshes in their home. We took walks on the Irish coast, visiting some of Donal’s favorite places and talking about him as if he were there. We even stopped in at the palliative care center where he had been cared for in his final months, visiting with his nurses, who spoke of him like a little brother they missed. On one final excursion, we took a boat out to Skellig Michael, a crag jutting out of the water off the Irish coast and considered a holy site. Atop the rugged rocks, Celtic Christian monks built a monastery over a millennium ago. Elma, nervous about my weakened leg, followed close behind me as I made my way up the steep, slick stone path with Donal’s walking stick in hand. We made it to the top and wandered silently through the cloisters, shrouded in mist.

Back at his home, we spent time sitting in his bedroom, with Elma showing me his keepsakes, which had remained mostly untouched. As a parting gift, she gave me a medallion with a saint on it, one that I did not recognize. It was Saint Peregrine, a thirteenth-century Italian who is the patron saint of cancer patients. At the age of sixty, Peregrine developed a cancerous tumor in, of all places, his leg. While deep in prayer the night before an operation to amputate the limb, he had a mystical vision and was miraculously healed of his cancer, although a visible scar remained; in hagiographic icons, he is depicted baring his robes to reveal his wounded leg. For the remaining few decades of his life, he roamed the countryside healing others; the name Peregrine comes from the word “pilgrim” or “wanderer.” As if there weren’t enough synchronicities rippling through my encounter with Donal and his family, Elma pointed out one final one: Peregrine’s feast day in the Catholic Church, which is the same day that he died, is also my birthday – May 1.

Over the past thirteen years, Donal’s legacy has continued. Each year, around the anniversary of his death, roughly 2,500 students from across Ireland convene for a day-long gathering at the Shrine of Our Lady of Knock, a pilgrimage site in County Mayo, and hear about Donal’s life and his message of hope. Each year, Elma is a keynote speaker, encouraging the young people, some of whom weren’t yet born when Donal was alive. Today, the gathering is among the largest annual Catholic youth events in Europe.

In the years since crossing paths with Donal, I have been making my own pilgrimage, finding my way into a vocation that I could hardly have envisioned at the time: psychology, oncology, and palliative care. As I look back, I see the trailhead where this path began: my encounter with Donal and Peregrine. They have remained with me since – the three of us ambling along the path, each with a slight limp, seeking out the ailing ones.