Recently I sat around a restaurant table with my grandmother, my mother, and my two-year-old daughter. We had a photo taken of four generations enjoying a meal together. My daughter and I had had the privilege of spending the week with my mother and hers, and I was struck by how lucky my daughter was to get to spend time with her grandmother, let alone her great-grandmother.

And I wondered, with delayed childbearing increasingly the norm, how much will our generation’s children get to experience the same?

I was greatly shaped by my grandmother. I spent my summers at her dining room table, where she would read the news with me and cultivated in me an interest in current affairs. She relayed and continues to relay countless stories of family, travel, and history, stories that would otherwise be lost to me. I’ll never forget an aunt scolding me not to let my grandmother see me cutting the greens off the strawberries, because I was wasting so much berry. My grandmother grew up during the Great Depression, and to this day despises waste of any kind. I frequently find myself in my own kitchen finding ways to save and reuse because of her example.

My great-grandmother, who I also had the privilege of knowing for most of my childhood, was 17 when she had my grandmother. My grandmother was 22 when she had my mother. My mother was 30 when she had me. And I was 27 when I had my daughter. The average age for a college-educated woman to have her first child today is 30. At my obstetrical practice, at the hospital where I had my baby, and at my pediatrician’s office, I was the youngest mother they had ever seen. In their careers. Admittedly, I live in a city where women are highly educated and career-driven, and thus delaying childbearing well into one’s thirties is the norm, but even so, times have changed.

Though most can see the trend of delayed childbearing illustrated in their own family trees, the overall numbers remain striking. In the past four decades, the proportion of first children born to mothers older than 35 has jumped from 1 percent to 15. The number of first children born per thousand women between age 35 and 39 increased by 25 percent, and the same figure jumped 35 percent for women ages 40-44. Overall, there are nine times as many first children today being born to women ages 35 and older than there were four decades ago.

There are certainly documented benefits to marrying and having children later, especially for college-educated women. Women who wait a bit to have children are more likely to make more money, and less likely to get divorced or to have had a child out of wedlock. But I wonder if there is a drawback that many aren’t talking about: With two generations of women now delaying children by a decade or more than previous generations, are babies being born today less likely to know their grandparents and develop relationships with them, especially before they enter their years of decline?

I thought the answer would be a straightforward yes, but in fact another demographic trend is pushing in the opposite direction: increasing life spans have actually made it more likely that children will know not only their grandparents, but their great-grandparents as well. One demographer at the University of California, Berkeley, predicts that almost three in four eight-year-olds will have a living great-grandparent by the year 2030, something a Census Bureau official calls a “great-grandparent boom.”

Delayed childbearing means that children are increasingly experiencing older grandparents.

But even if people are living longer, delayed childbearing means that children are increasingly experiencing older grandparents. (Of course, many other factors, such as geographic distance, will affect the relationship of future children to their grandparents, but age is one important factor of increasing salience.) Having seen my grandparents move from their active years through old age, immobility, memory loss, and even death, I can attest that the relationship children have with their grandparents is entirely different when the grandparents are in their sixties as opposed to their eighties. And while there are certainly virtues to knowing and spending time with an elderly person who needs great care and has suffered memory loss or other illness, there is nothing like knowing and spending time with your grandparents when they are younger. That is when grandparents are most able to teach, enjoy, and interact with their grandchildren in the most dynamic way.

It’s also when grandparents are most able to help with childcare. This is yet another factor I think about constantly. Most women I know who have careers and children are only able to combine the two because they receive help from their own mothers. One friend’s mother was the primary caregiver for my friend’s son from the time her maternity leave ended until his first birthday. Another friend was only able to do a Supreme Court clerkship with a newborn because the two sets of grandparents took turns acting as full-time caregivers. Another friend’s mom picks up her grandkids from school every day. My own mother was the only reason I was able to leave my then nine-month-old daughter to take advantage of the journalistic opportunity of a lifetime overseas. My and my friends’ experiences are not entirely unusual: According to Census data, as many children under age five in America are cared for by grandparents as are cared for in daycare facilities.

But barring unforeseen advances in health care, delayed childbearing will likely change this. Say a woman has a daughter at 35 and that daughter has a child at 33. That makes the first woman nearly 70 when she becomes a grandmother, when it is typically far more of a strain to help with a newborn than it is at age 55. These changing dynamics raise interesting questions about how tenable work-life balance will be for a coming generation of women: by the time they’re having children, their mothers are likely to be both older and more career-oriented themselves than the mothers of today’s working women.

The active involvement of grandparents isn’t only good for parents and children: older people value and benefit from it as well. A Pew study on aging in America found that people 65 and older listed “spending time with family” and “spending time with grandchildren” as the two biggest benefits of aging.

Thinking about the age of one’s parents when contemplating when to start one’s own family is probably akin to new college graduates making 401k calculations as they start their first jobs. But investing in family earlier than much of society would have you think is “good” may bring compound rewards later, for every generation.