Mid-summer, 2007—we were walking to the neighborhood park. Col, then two and one-half years old, was perched in our rattletrap stroller, while Rose, 4-months-old was cinched to my chest in acres of fabric. The cache of supplies required to keep two small people alive until nap time bulged through the duct-taped hole in the stroller’s cargo area. Sidewalks exhaled waves of heat.

Col was busy testing some vague law of physics by grinding his sneakers against the spinning stroller wheels, while Rose was grunting and scritching around her cloth nest, raising the temperature between us about 800 degrees. I was delivering a pep-talk to myself about enjoying the moment but really was hoping to find a 6-pack tossed under the bushes or at least some adult conversation by the swing set.

We ran into a friend and her two children, ages 4 and 6. They were walking to the trolley stop with nothing more than the small purse swinging off my friend’s arm. “We’re going downtown for smoothies!” the 4-year-old announced. I squinted in the dazzling sunlight at the trio, who could have been Peter, Paul and Mary singing “If I Had a Hammer” for how exotic and fanciful they appeared.

My friend smiled at me, the empathetic grin of a mother who had trudged through the wilderness of sleep-deprivation with a diaper bag chafing against her hip. “It gets easier,” she said. “Actually, it just changes—less physical, more mental.” And then she sauntered off with her ambulatory, verbal children while I hobbled down to the park, a smear of sweat blooming between Rose and me.

Yesterday Col and Rose, now 6 and 4, built a Lego hospital and queued up a line of mini people waiting patiently for doctors to mend their broken bones. I wandered around idly wondering how to help, until I realized my help wasn’t needed. So I scrubbed the fridge and made mayonnaise while my heart sang a little tune called it’s so awesome to have children who play independently but still love to get a butt-squeeze from Mama.

And then something in the air changed imperceptibly—a small molecule of snark landed in Rose’s eye and she leaned into the Legos, knocking the whole creation down. Col was heartbroken and mad, and I was called out of my domestic smugness to mediate, to furnish the right words—the ones that would invoke instant empathy and resolution—the ones that I wish were always on the tip of my tongue, but instead, seem to be floating around the next zip-code.

Col’s been appearing at my bedside in the morning, wide awake and slightly burdened with deep thoughts that perhaps rush in to fill the vacuum of his waking mind. Things like, “chicken eggs aren’t exactly meat, but they’re not exactly plants either, Mama.”

This morning he wondered at 6:30 am, “You know how there’s gravity but then also there’s like this other thing that makes us not fall off Earth because it’s spinning?”

For a second I remembered that for years all that was required of me in the morning was to stick a boob in someone’s hungry little mouth.

“Centrifugal force!” I called out, relieved, because last week we had to call my dad for an explanation of why water evaporates (“it’s not true that air has a suction in it,” Col was pretty sure, “but then the water just disappears!”)

And there’s the trickier stuff, like when Rose told me “I don’t like him,” about the boy who spit at her last night. And I felt my heart clench a little and suggested that maybe she “liked him, just not what he did.”

When Rose cries “it’s not fair” because Col’s hair doesn’t get all tangly or because baby starlings are bigger than their parents, the potential responses scrowl across my mind like an intimidating multiple choice test from high school. And none seem exactly right…or exactly wrong—it’s like I’m in the Zen Koans for Parents class and the correct answer is both: all of the above and none of the above.

But it’s more like the syllabus keeps changing and I’ve finally mastered pureeing baby food but we’re actually onto planetary science, high-level sibling mediation, and the drama of girl-cliques.

I’m so grateful to be growing alongside these amazing children; I just wish someone would slip me the Cliffs Notes every now and then.