I always expected to be a mom. As a kid, I loved taking care of other children. I was a baby sitter, nanny, camp counselor and a teacher’s aide. I even asked about maternity benefits on my first job interview. I had no doubt I would have children one day.

While still single and childless in my 30s, I became an aunt. I used all my saved-up maternal muscle to love and cherish my nephew and then my nieces who followed. Still, to some parents — thankfully, not my nephew’s and nieces’ parents — my role as an aunt didn’t mean much.

“Being an aunt is easy,” said a mom I met at a dinner party when I shared a story about my baby niece. “You play with the kids and as soon as one needs a diaper change, you’re out of there!”

Not true. I had changed my fair share of diapers.

Other parents were simply insensitive: “You’ll never really know love until you have your own baby.”

But I knew love. While my fertility waned along with my hope for motherhood, my then-2-year-old nephew exclaimed in a moment of growing self-awareness: “Auntie Melanie, we’re family!” Even this small child knew my love for him.

And in response to those four little words from that little boy, I set out to change the way we look at one of the most misunderstood, undervalued, and fastest-growing cohorts of American women: the childless aunt. Eight years ago, I launched Savvy Auntie, a lifestyle brand in celebration of modern aunthood. I dubbed the primary niche of women it serves: “PANK” — or Professional Aunt No Kids.

Today, 48 percent of women of fertile age are childless, up 35 percent from 1976. In a 2012 national joint-study by Savvy Auntie, along with Weber Shandwick and KRC Research, we found 23 million North American childless women — or one in five women age 18 and up — have a special bond with a child in their life, by relation or by choice through friendship.

And it’s a generous cohort. The average PANK spends $387 on each child in her life, each year, while 76 percent spend over $500 on each niece or nephew. That money isn’t spent only on the latest cool toys or greatest travel adventures; 34 percent of these big-hearted aunts contribute financially to a child’s education. They are also supportive of the parents; 45 percent have given gifts to parents to help them provide for their children.

While parents are stretched to their limits, PANKs are happy and able to offer support to the children in their lives in meaningful ways.

Yet, despite this, we live in a “Mom-opic” world with a myopic view of womanhood as motherhood. We live in a society where the latest celebrity birth is headline news and marketers brand moms as heroes.

Earlier this month, Andrea Leadsom, a British politician vying to be prime minister, went so far as to suggest that being a mother gave her more of a stake in the future than her rival Theresa May, who is childless. (Leadsom later apologized, and May got the top job.)

Motherhood is as much the “norm” as it is aspirational. To become a mother, it’s understood, is to find fulfillment and happiness.

Evidence, however, shows the reality is far different.

A study of the “happiness gap” between parents and non-parents, to be published in the September issue of the American Journal of Sociology, found that among 22 countries, parents in the US are the least happy relative to non-parents.

“Parenthood is onerous in the US,” says study co-author Dr. Robin Simon.

Parents feel family-work policies aren’t substantial enough. Meanwhile, many non-parents feel burdened with extra work when a parent leaves the office early or is on maternity leave.

But there’s a simple solution that benefits both groups. In countries like France, Germany and Israel, where there is a collective sense of responsibility for raising children and non-parents are valued as playing an integral role in the family village, the “happiness gap” is narrow or even nonexistent, according to Simon.

In other words, when childless aunts and uncles are a welcome and valued part of the family, parents are happier — as are the non-parents. The result is a double dividend.

While parents are stretched to their limits, PANKs are happy and able to offer support to the children in their lives in meaningful ways.

They may be secondary caregivers, but with their emotional, financial and material gifts, not to mention their quality time and positive influence, these aunts play a primary role in the vitality of the family. If parents in the US want to feel happier, the first step is to value and embrace their kids’ childless aunts and uncles as part of the family unit.

A good place to start is national Auntie’s Day, the day I established in 2009 that falls annually on the fourth Sunday in July. Like a Mother’s Day for all the other mothers in a child’s life, Auntie’s Day is set aside to celebrate aunts. When I asked other Savvy Aunties on Facebook what they hoped to receive on their “day,” they replied that acknowledgment was all they needed. Whether it’s a handmade card by a young niece or nephew, a text from a teen or a call from a parent, appreciation goes a long way.

Now at 47, I know I won’t be a mother, but I’ve come to understand that there are many ways to “mother” and that aunthood is a gift. I hope parents and their children will celebrate Auntie’s Day as a way to recognize just that. Turns out, we’ll all be happier for it.

Melanie Notkin is the founder of SavvyAuntie.com and national best-selling author of “Savvy Auntie: The Ultimate Guide for Cool Aunts, Great-Aunts, Godmothers and All Women Who Love Kids.” Boy Meets Girl® x Savvy Auntie® limited edition tee, available on www.boymeetsgirlusa.com.