My younger daughter, Megan, recently sent me a text which said “thanks for being my Mom.” I quickly and instinctively texted back, “It’s the greatest privilege of my life.”

A privilege, but not an easy one. Being a mother is the hardest thing I’ve ever done; there’s a lifetime constancy required of it that I never understood — not, that is, until it was staring me down. It sounds trite but there really is no script, no roadmap. For me, learning to be a mother was more akin to crawling around in the dark looking for something… than what I had been led to expect from the reassuring words in the parenting books.

It’s as a mother that I have been challenged the most; challenged to learn, to stretch, to grow, to forgive, to be patient. And perhaps the most difficult part: to accept, accept that I no longer have control, that my children have to make their own decisions — and their own mistakes, as obvious as they may appear to me. (If I am honest with myself, my own mistakes haven’t always been obvious to me, either.)

Read More: How to have an Irish Mother's Day

As I responded to Megan, my thoughts turned to my own mother, Mary Raftery, an Irish immigrant, who passed away several years ago. While our lives were profoundly different — as different as my daughters’ are from mine — I was struck by how similar were the tugs and pulls, the inherited life lessons, across three generations of women.

Maureen’s parents, Mary and William Mitchell, 1948. (Photo courtesy Maureen Mitchell)

Maureen’s parents, Mary and William Mitchell, 1948. (Photo courtesy Maureen Mitchell)

In 1947, my mother boarded a plane at Shannon, at the time an airstrip nestled in hayfields, to fly to New York City, where, as so many Irish girls had done before and since, she became a nanny. While it may seem simple today, even a cliché, hers was an act of tremendous courage.

Despite a few years working in England, my mother was a simple farm girl, with at best an eighth-grade education, and only distant cousins in NYC to welcome her. (She would not go home again for 25 years — by which time her father had died, her siblings were adults, and much of the Ireland she’d known had changed beyond recognition.)

Read More: A fond farewell for my Irish mother - the light of our lives

My mother’s life was defined not by warmth or nostalgia, but rather by grit, raw intellect, and her own brand of determination. Her philosophy was simple: if you had enough to eat, a warm bed, and clothes to wear — some of which she’d lacked in her early life — you had it made. Her motto was simple: “No one died, how bad could it be? Keep going.” There was little tolerance for complaining. One of her more memorable lines erupted while admonishing the publicist for Frank McCourt’s Angela’s Ashes — “What was he complaining about, he had shoes!”

The house where Maureen's mother grew up

The house where Maureen's mother grew up

It’s fair to say that my mother’s unsentimental, instinctive nature profoundly influenced my ambitions, career and life choices. Now I see how they have in turn shaped my millennial children’s lives, ambitions and decisions — filtered by my own reactions, and amplified by my own actions — in that eternal generational play of mothers and daughters.

Looking back now, my memories of motherhood are many and mixed. There are the very sweet memories that I cherish: falling head over heels in love with each of them for the first time, taking them to Paris, Sunday-evening picnics in front of the TV, and so many others. But I was often exhausted, confused, anxious as well as disorganized, with the ever-present feeling of flying by the seat of my pants. Being a mostly single mother, with complete financial responsibility, did not make it any easier.

Read More: Facts and figures about Irish mammies for Mother's Day

My mother was present in their lives, holidays, school events, birthdays, and occasional baby-sitting. Age mellowed her somewhat, and she enjoyed being a grandmother. But what shaped her was never far, and there was little tolerance for any sense of entitlement.

My girls give me much to be proud of and grateful for: they are healthy, with good careers and great relationships. They have life-long friendships (something which speaks volumes), and are passionate about their work and families. They are busy building their lives.

Maureen with her daughters, Fiona (left) and Megan (right) in Ireland, 1997. (Photo Courtesy Maureen Mitchell)

Maureen with her daughters, Fiona (left) and Megan (right) in Ireland, 1997. (Photo Courtesy Maureen Mitchell)

Perhaps best of all, I am a newly minted grandmother. And I want to see and know my granddaughter. I want her to know me, in the way that my girls knew my mother — and beyond. Despite the 3,000 miles that separate us physically, I am determined to be a constant presence in her (and in her future siblings’) life.

Decades ago, a wise Irish cousin summed up motherhood with an adage: “Enjoy them — they’re only on loan to you”! I have come to see the wisdom and the universality of that. Life is fleeting, we are all only on loan to one another.

Read More: Our favorite Irish mammy sayings for Mother's Day

This is a lesson that I am sure my daughters, and their own present and future sons and daughters, will come to learn — more easily, hopefully, than it was for a simple Irish farm girl who arrived on these shores so long ago.

Maureen Mitchell is the former President, Global Sales and Marketing for the asset management arm of GE and serves on a number of boards

Maureen (right) with her mother and daughters. Maureen Mitchell