We all have one. Mine happened when Q was about seven weeks old.

We had just spent a lovely hour at Greenlake with some other new parents and babies from my childbirth class, walking, talking and sharing our adventures in early parenthood.

It was my first time using the stroller. I had one of those travel systems, and had miraculously managed to open the stroller part and get the carseat inside even though it had been about a million years since I learned how to do that at the store way back when I was six months pregnant.

I was definitely nervous about getting it all to fold back up and go into the car, but somehow I easily transported Q in her carseat into the backseat, and folded up the stroller in a few seconds, slipping it in to the trunk with one hand as I waved goodbye to my friends with the other.

I felt giddy with relief and almost cocky. Ok, I was totally cocky. After so many weeks of sleepless, interminable days where I seemed to invent new ways of screwing up by the hour, I had suddenly pulled off a major outing without a hitch. I started up the car, carefully pulled out of the lot, and began the drive home with a big grin on my face. At some point, I turned the radio on and sang along, I think, to Salt N Pepa’s Shoop. “Oh my goodness. Girrrrrl look at him. And he’s coming this wayyyy!”

I sang and cooed to my baby all the way home, feeling ssssoooo gggooood about myself, which should have been a red flag. Q’s strange grunting noises should have been an even bigger red flag, but newborns make so many weird noises, I willed myself to let it go.

Stopped at a red light just a few blocks from my house, I finally had the chance to turn around and really look back at my baby. With horror, I realized she wasn’t buckled in. Of course. When I was using her carseat as a stroller, I’d unbuckled her to put her into the frontpack, and then I’d just set her back in. The grunting noises? Those were because she was all scrunched up into the side of her carseat without the straps holding her in properly.

I sat at the light for about 20 million years, one arm back over my baby, tears streaming down my face. Cars seemed to breeze by at 75 miles an hour and I prayed hard that we wouldn’t get rear-ended. Finally, I turned, drove the short distance home, parked and raced back to grab her. I ran into the house sobbing and made my husband promise never to let me take her out again.

I mean, yeah, I didn’t set her carseat on top of the car, or leave her at the park or anything truly criminal. But boy did I go from Supermom to Mommy Dearest fast. I’ve since learned that that particular leap is a pretty common one in mommyland. I’ve also learned that around these parts, whenever something seems too easy, it’s usually because I’ve missed a step.