He was only 15. His older brother Floyd was working next to him on the far steel beam. The hot sun beat down on the two of them during that summer of 1933. He had moved hundreds of miles from the small town of Albert Lea, Minn., to New York City, joining the rest of America in search of jobs during the Depression.

The two brothers worked feverishly on the railroad bridge, which would become part of New York City’s Triborough Bridge. More commonly known as “Triboro,” the bridge was made up of smaller bridges that connected the Bronx, Manhattan and Queens. He earned more in a week than he had made back home in three months, and spent it with as little regard as any teenager would, living it up with no pause toward the future. My grandfather—the kind, elderly gentleman who would always tell my siblings and me stories of fishing— wasn’t telling us his whole story.

Born in 1918, George Alvin Gunderson, my grandfather, had hid a story about his life that neither I nor any of his grandkids had ever heard before. The importance of knowing your family’s past never came across as important to me while growing up. Any questions about my grandparents could always be answered by my mother and father, who usually settled on one- to two-sentence answers. The time my two siblings and I spent at my grandparents’ houses was always reserved for playing cards and listening to the baseball game on the radio, not for digging deep into my grandparents’ pasts.

I can still hear the birds chirping outside that day as I sat opposite him in his cozy living room. It was May 26, 2003 when I set to the task of uncovering my grandfather’s hidden past while I still had the chance. The timid 84-year-old figure was transfixed on the mini tape recorder I placed before him. Today we weren’t going to sit back and watch television idly while the summer day crept by. No, today was different.

My grandfather had dropped out of school at age 7 to help his mom, dad and six siblings on the farm, tromping behind horses in the field while his friends attended class. He would be sent to different farms for the next five years to earn money for his family. At 12, he joined the Civil Conservation Corps, one of the programs Franklin Roosevelt created to help get Americans back on their feet. Earning $30 a week for his hard work, my grandfather helped his family scrape by until they could rebuild the life they had had before the Depression.

His golden ticket would come at age 15 in the form of a visit from his older brother Floyd, who came to visit the family from New York City. Even though my grandfather was underage, Floyd snuck him into the New York City company he worked for to work as a welder. In this single year, my grandfather established a new life in Manhattan, earning $300 a week before work got slow and he started a life as a cook in a small restaurant.

It was while working in New York City that he met his future wife. He stopped by a diner for lunch. She took his order, and the rest is history.

Where did all of this missing information come from? Had he just forgotten to tell me, or was he simply waiting for one of his grandchildren to ask him about more than his fishing trips in Minnesota? The house we were sitting in was a product of the 1950s, one that he had bought after serving in the Army for four years as a sergeant and later as a mess sergeant at Fort Riley.

Up until then, all I knew or cared to know was that he had served as a successful sergeant in the Army at Fort Riley and opened a restaurant after he was released.

In 2007, I had the opportunity to go to New York City for a week. I spent time in Brooklyn, the Bronx and Manhattan with friends. My grandfather had died a year earlier, and the grief from his passing had stayed bottled up in me since.

The entire week, while walking around and taking cabs and subways across the different boroughs, I wondered which of the many bridges my grandfather had worked on.

My friend Shirley, who lived in the Bronx, told me that I had already seen part of the Triboro bridge when I first came from LaGuardia Airport, and that I would see it again on my way to leave New York.

As the shuttle van drove across the bridge on the way back to the airport, I looked out in awe at the project that my grandfather had been a part of. It wasn’t the freighter railroad bridge part that was used primarily for commercial shipping, but it was officially a part of the grander Triboro bridge, and that was enough for me.

To be in the presence of my grandfather’s hidden past helped me reconnect his stories on tape to the life that he had lived. His history, which belonged not only to him but to everyone in our family, had come full circle.