Photo by JORGE LOPEZ on Unsplash

My mother-in-law passed away a years ago. She wasn’t an entrepreneur, or a business owner. But she was by far the hardest worker I’ve ever known.

Mom was born in Poland in 1958, in hard times. She knew what it was like to struggle, so she never took anything for granted. She taught her two daughters to do the same–to enjoy the good times, prepare for the hard times, and discover what’s really important in life.

Mom worked for a number of years cleaning offices and private homes. It was more than just a job for her; she cared about the people she worked for. When she needed to leave one job in which she cleaned the office of a high-level executive of a major car manufacturer, his secretary begged her to stay. She trusted Mom immensely, and had grown accustomed to their refreshing and encouraging chats. Mom left after all, but the secretary never lost contact, periodically stopping by my mother-in-law’s home for a cup of coffee. Mom had made a lasting impression.

Mom’s latest client was a blind woman, for whom she would not only clean but also do ironing and other small tasks. As Mom’s sickness progressed, Mom asked her daughters if they could take on the small side job because she wanted to see this woman taken care of. That was Mom, always thinking of others.

In addition to her cleaning jobs, Mom volunteered double-digit hours every month to teach. (She was a student of the Bible and offered to study it with anyone who was interested.) She said volunteering to help others gave her strength.

My wife and I often remarked that Mom was stronger than the two of us put together. When my wife’s grandmother started showing signs of dementia, Mom took her into her home and became her full-time caretaker. About a year later, my father-in-law’s mother had a stroke, leaving her partially paralyzed on one side of the body. The idea of putting her in a nursing home was brought up, but Mom couldn’t stand the thought.

After some discussion with the family, Mom decided to take my father-in-law’s mother in as well. My wife and I worried that it would all be too much for her, that she couldn’t handle that much work. She insisted she could. She was right. Mom tenderly cared for Grandma until Grandma died. She was happy to do it, and didn’t regret her decision for one second.

Throughout those years of caring for both her mother and mother-in-law, hours of volunteer work, and her small side job, Mom still found time for ‘personal’ projects– like knitting a hat for my little boy and girl, or making small gifts for friends. For mom, ‘personal’ still meant helping others.

A couple of years ago, Mom contracted an aggressive form of lung cancer, despite the fact that she never smoked a day in her life. She fought the disease hard, with multiple rounds of chemotherapy. Even in her last hours, mom was still thinking of others: She wouldn’t stop thanking the doctors and nurses working at her station, and she wanted all of us to meet them when we came to see her in the hospital. She was amazed at their ability to remain positive, kind, and compassionate, despite the nature of their job to see pain and suffering every day. They deserved recognition and appreciation. Mom helped give it to them.

Mom was by far the hardest worker I ever knew. But she didn’t work for monetary gain, or for her own pride. Mom worked hard because she felt it was the right thing to do, and because she wanted to help others. And everybody she met loved her for it.

Above all, Mom taught me the following:

Life can be extremely, surprisingly, disappointingly brief. Figure out what really matters, and then work hard for it.

Thanks Mom. I promise to try my best.

Enjoy this post? Check out my book, EQ Applied, which uses fascinating research and compelling stories to illustrate what emotional intelligence looks like in everyday life.

A version of this article originally appeared on Inc.com.