I’m 28. He’s 85. Our time together has taught me a valuable lesson about friendship

Mr. Fred signed off his latest page-long, handwritten letter, “Thanks again for your friendship.”

I read that line with a smile. Undeniably, he was my friend, despite the 57 years that stood between us, the different lives we’ve lived — his much longer, mine much shorter — and whatever we do or don’t have in common. Friendships are funny that way.

Ours began when I knocked on the door of a glass house that belonged in the Swiss Alps yet was outside a small town in central Louisiana, nestled among curving country roads and cotton fields.

When the door swung open, a jaunty stranger with gray hair and a wide smile greeted me — the 25-year-old life story writer his daughter had commissioned to write a keepsake biography for the family — and shut the door behind us.

“May I show you some treasures before we begin our interviews?” he asked and led me to a room lined in bookshelves. He pointed to a wooden canoe he and his best friend had carved in retirement, a silver cup on which his name was engraved and which he had dinted as a toddler, and the chest in which his great-grandfather’s belongings had traveled from Germany to the U.S.

From there, we headed to the kitchen. While Mr. Fred brewed a pot of coffee, I sat at the round table, turned on my laptop and extracted my questionnaire. Once we both had full mugs, we began his first interview.

When I reached my tenth question — “Do you have any vivid early memories?” — he nodded and swatted a tear. He proceeded to recount hearing the news of Pearl Harbor’s bombing on the radio in Audubon Park. “I was just 4 years old but could sense the secure world I’d known only minutes before collapsing.”

As we continued, I was surprised by his openness. I had organized my questionnaire in an attempt to build comfort and rapport over time. Yet here was Mr. Fred, sharing evocative sentiments within minutes of getting started. This went on for hours as we sat at his round table in his perfectly square glass house.

I eventually learned the story behind his home. After he’d worked enough grueling years as a contractor to finally afford a bigger home for his wife, Patsy, and their five children, they had this dream home built.

Again in tears, which became a reoccurrence during our interviews, Mr. Fred said, “While this place was under construction, Patsy and I sat on the step, overlooking the sunken living room, and she asked, in wonder, ‘Did you ever think we’d have something like this?’ I didn’t.”

I found myself looking forward to interviewing Mr. Fred more than usual; I simply enjoyed his company. Outside of interviews, we’d talk nonstop, as if we were old friends catching up after years apart. We’d take daily lunch breaks with him driving us into the nearest town for Mexican food or McDonald’s. He’d never let me pay, insisting he “treat” me in the same tone as my grandfather would. I dare not argue. After lunch, we’d detour, driving by his elementary school, the starter home he and Patsy brought their babies home to, and the hangar where he kept the plane he still flew.

The more I got to know the 83-year-old Mr. Fred, the more his past clicked into place with his present. I understood how the awe-inspired boy building model airplanes grew into the young man scrounging spare change to afford flying lessons. I could see how the tender father whose eyes welled with tears when he spoke of his pride in his adult children was the same father who, 61 years earlier, had been forever changed when he first held his eldest child and experienced what he called “wonderful magic.” I could see how the widower who lost Patsy eventually remarried another widow, Linda, who understood his suffering.

At that round table, he revealed his most excruciating memories and most joyous moments. I listened as he unveiled his early memories, experiences as a young adult, family life, career and recent years. When he struggled to remember specifics about when his children were small, since he was working so much, I assured him I could email his children to elicit some fond memories.

One of his children wowed me by sending three single-spaced pages of reflection, confirming what I already knew about Mr. Fred — he was an authentic, compassionate and outstanding human being.

On the final day of interviews, I asked Mr. Fred if he had any life lessons he wished to impart to his children and grandchildren. That is when he told me about true gifts.

He leaned forward in his seat, looked me straight in the eyes and explained, “A true gift is one which has no strings attached. Many gifts, even with great intentions and great outcomes, become less true along the way. I try when I give to make the gift a true gift with no personal gain or conditions.”

I was moved by the concept. In that moment, I knew the notion would stay with me forever.

Long after our five-month working relationship ended, Mr. Fred and I kept in touch. Every month or two, one of us would call the other. We’d talk about what was on our hearts — his adventures with his children, stepdaughter’s cancer treatments and travels with his wife, and my writing, hope to start a family, and eventually, my husband’s and my anticipation of our first child. We’d also talk of history and poetry and genealogy.