Olessa and I worked together years ago and were longtime friends. I had never met Siobhan. But our time together each week felt like a small miracle. I didn’t have to explain my strange new self to them. We were all obsessed with our babies. We were all overwhelmed. If one of us started crying for no reason, the others just passed her a tissue and kept talking.

I trust these women more than anyone. We take advice from each other before doctors or parenting books. We often make different decisions for our children, and yet there is never a hint of judgment. As we’ve found our footing, our conversations have moved to topics beyond babies. There’s a built-in intimacy there, and so it feels natural to talk about other important life events too. I hope it worked out this way for those women I eavesdropped on at Le Pain Quotidien. Maybe by now they’re all getting some sleep, and they joke about the time nobody could remember Kate’s name.

A friend told me recently that she still talks every day to the mothers she leaned on when their now-10-year-olds were newborns. Some of them, she said, were people she knew beforehand, but this shared life event, unlike any other, accelerated their bond. I thought then of Steph, who introduced Cathy and me. She was only a casual acquaintance until we connected over being pregnant. She was so generous with her knowledge and time. She sent an enormous spreadsheet detailing all the things I needed to do and plan and buy before the baby came. Our friendship was solidified when I asked her what the frozen maxi pads on the list were for, and she calmly explained in great detail.

Steph continues to play this role for Cathy and me. To a new mother, a woman with a child a few months older than yours is a prophet. Most recently, I asked her if babies can eat tuna salad and when my child will stop being a human wrecking ball, destroying everything in his path. (The answers were Not a lot, but it’s good to try new things and Never.)

I’m almost 37. It’s been a while since I made so many close friends all at once. When I think back on it, circumstance was at the root of every lasting friendship I’ve ever had — the girls I grew up with just happened to live on the same street as me; my college friends just happened to choose the same school. As I get older, more set in my ways, there’s less room for these chance meetings to occur.

I’m now more than halfway through my second pregnancy, and although I’m much better prepared this time, I’ve been feeling wistful that my original new mom friends won’t be along for the ride. You need people who are in the trenches with you because you forget so fast what babies are like. Already, I cannot recall what a child does at four months vs. five months vs. six. Recently, I got an email from a woman who is due two weeks after me. We’ve long been fond of one another, but we’ve never hung out one-on-one or even exchanged phone numbers.

Will you be my text-neurotic-things-to-every-day friend? she wrote. It’s her first baby.

I responded right away: Of course.

J. Courtney Sullivan is the author, most recently, of the novel “Saints for All Occasions.”

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