The lines that used to appear as a parentheses to my mouth only under close inspection, and only when actually smiling seem suddenly—though I know it’s not “sudden”, because getting older isn’t ever sudden—more pronounced. These days I wear sunglasses to shield my eyes from the sun, but mostly to hide the crow’s feet around them and prevent the onset of more wrinkles. Lately I’ve noticed every now and again what looks suspiciously like a gray hair, or, maybe, as I try to convince myself, just maybe, it’s a very light blond hair I suddenly started getting—even though my natural color is more a mousy brown than blond.

This getting older thing? It’s…well…I am not entirely sure what it is. Except that it happens. You go your whole life hearing people marvel at how fast the years go by, at how fleeting the days are, how puzzlingly quick the progression of time is. And you smile and you nod and you think, “How sad for them. But me? I have all the time in the world.”

And then suddenly you don’t.

Not because of a terrifying diagnosis that serves as a sort of wake up call, but because it’s clear now, those older and wiser and more advanced in years were not just waxing poetic at the speed of time. They were trying to impart their acquired wisdom to you. And you missed it. Because you thought yourself exempt from the speed of time and how sneakily it passes.

It’s so cliché. When other people talk about it. But it’s real and it’s jarring and it’s confusing when it happens to you. When you get older. When you look back and almost imperceptibly shake your head at how what felt like yesterday was actually decades ago.

This is what I remember.

Sitting with my sister and my mom and dad at small table at Disney World, enveloped in humidity, tired from the heat, and being told I was going to be a big sister, crawling into my mom’s lap and wondering aloud if I would still be her baby.

I remember that baby brother arriving and the mangy, ratty Big Bird puppet I would use to put on shows for him, getting him to laugh—or at the very least, stop crying—and proudly bringing him for Show and Tell in kindergarten.

I remember my sister and I spending the day at an Amish farm in eastern Pennsylvania, at the home of family friends of ours where we had our hair braided and milked the cows, and jumped from haylofts and pretended, for the day, that we could live in this quaint farmhouse, with no electricity, and clucking chickens and horse and buggies.

I remember themed birthday parties and celebratory dinners at Outback, beach vacations and mountain getaways. I remember how slow the summer was, and how far away adulthood seemed.

I remember walking down the aisle to a man I promised forever to, but having no earthly idea what that even meant or what exactly we were promising.

I remember watching that man hold our babies. His tanned arms, strong and muscled in their tender grip on their tiny bodies.

I remember running my fingers over our babies’ fuzzy arms, and backs, and marveling at how their delectable rolls could so easily be smoothed, and no trace of a wrinkle or a line left where I had rubbed their skin. How brand new they smelled and looked and how surprising it was to experience this new life, and simultaneously have a greater sense of my own mortality.

I remember the moments my childhood and theirs started to meld together, the resurrection of feelings and emotions when reading The Lion, The Witch and the Wardrobe with them for the first time, going to Disney World, the beach, the evenings spent at the pool. I remember what feels like my own memories, but now I wonder if they were actually theirs’. If in the raising of babies and the growing of children you do more than pass along what you know and impart what you hope, you pass down your recollections, and this generation behind you becomes the melting pot of the memories from generations before. They are collectors of legacies. They are holders of heritage.

And that makes getting older easier, I think.

Today I turn 36. Thirty-six. What in the actual world??? And it isn’t that I don’t like getting older, it’s that I wonder how it happened exactly. Because that baby brother arrival, I remember so clearly. And the magic from that Amish farm visit, feels so close. And the person in the mirror sort of resembles the person I remember seeing, but those lines, those pesky lines around my mouth, in the corner of my eyes, in the space above my nose, where did those come from?

I rubbed the backs of those boys last night. And I smoothed their cheeks, though the rolls at their ankles and wrists have disappeared and the peach fuzz on their upper backs is nearly gone. I noticed how much more strained the arms of my husband are now, when these boys leap into them. That their bodies, once fitting in the crook of his arm, now envelope his in a wrestling match, and a pool fight.

I want to remember as much as I can. All of it. As much as possible. I want to treasure these things inside. And I want to be a voice that the generation behind me will smile and nod at when I get a faraway look in my eyes and recall how fast it all went by, knowing they won’t believe me, knowing they’ll think themselves exempt, knowing what I say won’t really matter. But doing it anyway.

To those farther along than me, I’m sorry. I should have listened better. I get it now. It’s fast. And it feels like a sucker punch. And I understand what I didn’t before. You were right. Time is ruthless.

To those behind me, humor me for a second. Believe me when I tell you it will happen to you too. That you will suddenly find yourself at an age you imagined at one point, but in your mind saw yourself feeling much more adult than you actually are, and wonder if the world can see how ill equipped you are to have such adult responsibilities. You will look back and you will remember all you can, and you will surprise yourself at what memories got fuzzy around the edges, and what things stuck. There is a coming a day when it will hit you how fast time is. It doesn’t have to be scary. But let it be a reminder to you. To make it count. To rub the backs of babies, and to impart what you know. To hold close the stuff that matters and to let go of things that don’t.

And embrace the wrinkles. As much as possible. They’re happening. But make them wrinkles that testify to a life lived well, and not a life passed by.