When I was growing up in the 1960s, sometimes a classmate would mention having an aunt, then quickly add, “well, she’s not a real aunt.” The woman was a family friend.

I learned there’s a difference between a genetically related member of the family and an intentionally included one. I envied families with both.

My family was small: two parents, two children. The only nearby relative was my maternal grandmother. As a child, I greedily fantasized about having additional people in my life to give me nice things for birthdays and Christmas. Later on, when gathering emotional support mattered more than acquiring stuff, I longed for more sources of guidance and affirmation.

I had several aunts and uncles, but my parents were not particularly close — emotionally or geographically — to their siblings. My parents never entertained friends or neighbors, I had to beg for permission to invite my classmates over and I never had a birthday party. Part of this isolation might be because m parents came from Scotland but were Italians. Their outsider status weighed heavily upon them. Only reluctantly did they allow anyone into the house — even children.

As a result, my parents, younger brother and I became a tiny tribe unto ourselves.

I lived at home while working on my degree in biology. After graduating, I found a job and my own apartment. Before long, friends began to pair off and start families. Whenever a baby arrived, I visited, if I could, modest gift in hand. I revisited the concept of the honorary aunt — this time, from the other side. Try as I might to figure in a wee one’s life, I never did. For one thing, my late 20s and early 30s were highly mobile times. Establishing those crucial bonds with young children and their harried parents seemed contingent on sharing an area code. I was also excluded because I had no child of my own, either to bring along for play time, or to give validity to my words of reassurance or counsel.

I married in my mid-30s. Motherhood did not follow. Meanwhile, a new set of friends embarked on that phase of life. When they shut me out that time, it hurt even more.

I see parents everywhere with too little time. Their children hunger not only for attention but the right kind of attention. Many grow up in nuclear families like mine. But there are encouraging signs, in popular culture and elsewhere, that “family” is being redefined. There have long been blended families. Now, same-sex unions are part of the discussion. All sorts of other households are popping up as well. If society can embrace these signposts of diversity, why don’t more couples ask their child-free friends to pitch in?

Child-rearing is the hardest job in the world to do well, yet so many of us expect two people (or one) to do the lion’s share of the work — and take 100 percent of the credit. It used to be different. All women, no matter their age, reproductive stage or status, cared — or at least looked out — for children in the group. Every woman was somebody’s auntie.

I wish the best of those days would return.

I attended a lecture by Harvard biologist Edward O. Wilson’s on his work “Sociobiology: The New Synthesis.” According to his model, shared genes make self-sacrifice worthwhile. If you die saving a sibling, for example, you could still keep about half of your genes in the breeding pool. Few were comfortable with that idea. For one thing, it said nothing of free will or culture — moral teachings included.

Human beings — and many other animals — do not store, transmit and improve information through genetics alone. We use culture. We’re driven to do many of the things we like doing because we want to give, acquire or develop knowledge. Art, science, history, journalism, politics, religion: All permit sharing. These tools transcend family and community. A person can benefit from an invention or discovery, song or insight, from across town, across the world or even from a previous century.

Wilson’s theory failed to explain why many people risk their lives for friends or strangers. Or why people perhaps only remotely related, if at all, help their friends with their children — presumably giving them a greater chance of reaching maturity. The most obvious reason for sharing work is reciprocal altruism: You scratch my back and I’ll scratch yours.

But paying it forward may be a better reason for some acts of kindness. Shared culture can create a sense of kinship. For parents, that network should not be restricted to other mothers, fathers and grandparents — although it often is. Those without their own children are also valuable.

Aunties can give children additional trustworthy adults to look up to and expose them to different opinions and points of view. They are available to help if illness strikes the main caregivers. They can increase the child’s exposure to diversity, from customs to diet to lifestyle to religion and politics. This fosters critical thinking and empathy. And they bring more love into a child’s life.

There have always been women who could not have children, but intentionally foregoing motherhood has become a more common option. According to the 2014 U.S. Census, 47.6 percent of women go through their peak-fertility years (ages 15 to 44) without giving birth. A large number of these may never raise adoptees or stepchildren, either. But many want to be around children and share what they know, from math tips to heirloom recipes to foreign languages or customs.

Society will have to accommodate these significant demographic changes sooner or later. A segment of the population this large (and growing) is too big a resource to ignore.

I don’t regret not having children, but I wish I had had more children in my life. In my lonely 20s, having a friend’s kids greet me at the door, squealing my name and begging to play, would have been a breath of fresh air. And those nature walks I love to take would have been more special with a child or two by my side.

I want to leave something behind as much as any mother or father does. Perhaps one or more of my future books will be published and sell well, spreading my ideas far and wide. But a surer route to influence, however ephemeral, is one-on-one, in person. It’s also more immediately gratifying.

I get plenty of ideas and critical comments related to my work from nonwriters all the time. I welcome their view of the process — unconstrained by trends and undercurrents of competition. Perhaps parents could use an occasional bit of outsider opinion as well. I urge them to broaden their child’s circle of influence.

If I were to do it over — navigating the minefield of rapidly shifting family structures and friendships as we became proper adults — I’d be more organized and less intimidated by each new parent’s search for the company and advice of others in the same boat. Before the demands of their new life changed everything, I’d leave a note behind at their homes: Need help cooking for the week? Want someone to play dress-up with your preschooler? Have to explain where hamsters go when they die? Call me! I’ll always be here for you and your little one.

Louise Fabiani is a freelance writer based in Montreal.

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