My son works with me at our 120-year-old family business. I’m 72 and have been working there since age 12.

• Michael Petri began working at his family’s plumbing business as a tween.
• The odd jobs led him to enter the profession after college and become the majority owner.
• He is celebrating the firm’s 120th anniversary and said it is in safe hands with his son.

This story is based on an interview with Michael Petri, 71, from Brooklyn, New York, of Petri Plumbing. It has been edited for length and clarity.

I officially joined my family’s plumbing firm in 1977 at the age of 23, after graduating with a business degree from Villanova University.

The company had been at the center of my life since I was born, whether it was listening to my dad and granddad talking about its founding in 1906 or hiding in the park to avoid being called in to help.

I did the dirty work

I was around 12 at the time. No matter what tree I crouched behind, someone would find me and make me do the dirty work, like sweeping the floors or cleaning the trucks.

My younger brother, Gerard, now 68, entered the firm after high school while I waited until I’d left college.

Even in college, I had to help out. Once, I’d barely gotten off the bus for Christmas vacation when I was summoned to a shack in Coney Island.

Gerard said we had to go under the property to fix a pipe. “I’m not thrilled about this,” I said. I opened the hatch and stuck my head down into the basement.

I saw a thousand eyes looking up at me. They were rats. Dad got me to break some glass into a bucket and throw it at them so they’d scatter. “I’m not getting paid enough money for this,” I said.

I accepted a well-paid job elsewhere

Still, I persisted. Gerard and I were at the bottom of the totem pole. There was no special treatment for being the bosses’ sons and grandsons. We earned $30 a week.

Two years in, I was offered a good, well-paid sales job at a nationwide company with headquarters in Toledo, Ohio. My dad encouraged me to accept because he wanted me to spread my wings.

So I took it. But I didn’t so much as set foot out of New York. I waited for my flight at JFK airport and, at the last minute, ran to a payphone.

“I can’t do this,” I told Dad. “It’s not really who I am.”

So I went back into the field and eventually qualified as a licensed plumber.

I particularly enjoyed working on residential projects. As a successful tradesman, you need empathy. People often call you when it’s an emergency. You have to calm them down as you do the repair.

My son is following in my footsteps

Gerard was more into the commercial side of things, often on-site in office towers and hotels. However, I have always preferred working with private customers because of the human interaction.

Petri has gone from strength to strength. We now employ over 40 people. My son, Chris, left his internship on Wall Street to follow in the family footsteps in 2015.

He owns 49% of the business, and I own 51%. As vice-president and the operations manager, he’s taken things to new levels by embracing technology.

We’ve certainly seen some change over the last 120 years. A display in our office features the horseshoes used for horse-drawn carts in the early 20th century and lanterns before flashlights came along.

Legacy isn’t as important for younger generations

The longevity is hard to beat. The company has been through the Spanish Influenza, World War I, the Great Depression, World War II, the Korean and Vietnam Wars, up to 9/11, and beyond.

I’d love to say the company will stay in the family for another century. But legacy isn’t as important as it was for my generation.

In the meantime, I’m grateful to Chris for continuing to build a successful operation that the whole family can be proud of.