It was a blistering August day in Los Angeles. I fled the heat with my newborn son for that haven of air conditioned air: The mall. Shopping wasn’t an option — funds were tight for our little family. But the cool air and wide walkways were free (to us) and I could look, right? I nestled my tiny munchkin into his stroller for his first taste of American consumerism. I wasn’t the only one with that idea, of course; the mall was packed with heatwave refugees.

L.A. is not a super neighborly town. Oh, people are decent for the most part and often kind. But it’s not the sort of town where I often found myself in conversation with strangers in public. At least not when it was just me. I didn’t know it at the time, but adding a baby to the mix changed everything. Everyone wanted to talk. They had stories to share, advice to give, questions to ask, coos to coo. A tired-looking woman wrangling three energetic toddlers gave me a good-natured warning of what I had to look forward to. A tiny, wizened, white-haired great-grandmother related, in vivid detail, the difficult birth of her son — seventy-five years ago. I got unsolicited input on burping, diapers, family size, stretch marks, gender, feeding. (A side note: Despite what you hear about shaming nursing mothers, I nursed my children whenever and wherever they needed it and no one ever said a disapproving word to me. If they glared, they did it out of my line of sight.)

Suddenly, the barriers were down. I was part of a new world – I had the secret handshake, the membership card, the password: I was a mother with her baby. Of course, I knew that mothers had certain shared experiences that were different from those without children. I had spent the previous all of my life on the other side of that divide. I had experienced giving birth and felt how it changed me with respect to my son. But I didn’t expect how dramatically it would change me with respect to other mothers.

Pregnancy is training wheels. When you’re pregnant, your body becomes community property. Normally polite people feel free — compelled, even — to comment, advise, warn, discuss, congratulate, speculate, predict and inquire about your body in ways they wouldn’t dream of doing about, say, fat or a deformity or your salary or your skin color or even your shoe size. But pregnancy is a different animal – one on which it is always open season. When I was very pregnant, apparently my belly protruded so far through my personal space that it spilled over into public space; some people felt entitled to actually touch it. (Pro tip: Doubling over and grasping your belly as if in sudden, intense pain cures this instantly.)

When my baby was finally born, it took a while to see him as a separate being and not part of my personal body. Thirty years has done it, more or less. But for a while, he was still ME.

That day at the mall was the beginning of my entry into a new world, this new biological, emotional sisterhood. That elderly woman was like me – she had been young once, had brought squirming life into the world. Countless women around the world and throughout history have held a small, warm, damp body in their arms and felt their world transformed. Creating this new being was my hazing into a sorority going back to the beginning of life on Earth. I shared a new bond with queens and beggars, shamans and movie stars, cavewomen and astronauts, soldiers and refugees. Hell, on that day, I felt a bond with bears and cats.

This is not meant as a snub of non-members. There are lots of clubs I will never belong to. I will never have a daughter. I may never be a grandmother. I will never get into the club for men, Asians, twins or former Miss Americas. But my world was rocked when I got my mom card.

Now, my niece is expecting a baby. I can’t wait to welcome her to the club.