There comes a time in every parent’s life when they are faced with the sudden and shocking realization that their children are no longer children.

Monday morning I pulled an undershirt out of the drawer, and there at the back of the collar, just above the imprinted size and manufacturing information was the letter “L” written in black Sharpie.

Uh oh. It has happened. My oldest son’s clothes and my clothes are now so confusingly similar in size that my wife has resorted to coding our wardrobes to prevent mishandling. Like so many other of her schemes, the labeling was brought on by my complaining.

After Christmas, when each of us Wallace men received a new package of Hanes undershirts as gifts, I reached into my drawer, pulled out a fresh white T-shirt and slipped it over my head. Knowing that my workouts have been reduced to running, I felt sure that the snugness of the shirt was not caused by my rippling muscles.

I pulled it back over my head and discovered the truth: “M.” What happened next is somewhat in dispute. I may or may not have ranted like a lunatic about my children’s underwear ending up in my drawer, and I may or may not have made a statement such as “What’s next? Carlton’s Batman briefs tucked in with my boxers?”

Carla didn’t acknowledge my critique. She’s acquired the tone deafness that comes with 17 years of marriage. She just casually mentioned that I do most of the folding and putting away of the laundry. There is a fairly good chance that it was me who committed the heinous laundry foul of putting Barron’s mediums in my drawer.

Carla responded by doing what all mothers do: she relied on her resourcefulness and fondness for labeling to come up with a solution. So now, as a 40-something year-old man, I have been reduced to having my name written in my underwear like a third grader heading off to summer camp for the first time.

What I am discovering, though, is that her system is not consistent. While some of my undershirts have an “L” written in it, the boys’ shirts have a series of dots, or dashes, I can’t tell which. In the Wallace Family Underwear Morse Code, one dot means Barron, two dots means Harris and three dots mean Carlton. Except when it doesn’t.

Apparently when she was labeling our new shirts, she lapsed into other classifications. For example, one of Barron’s shirts accidentally has two dots with one of them marked through and the letter “B” written next to it. There is more written on this shirt at the nape of the neck than the fine print on a pharmaceutical ad in Reader’s Digest.

While I can usually eyeball the difference between Barron’s T-shirts and those belonging to his younger brothers, I tend to mix his and mine or Carlton’s and Harris’s. You would think a glance at the label would clear things up with the younger two, but when I have to look at the label, the Hanes people have made things inexplicably complex. All of the boys wear an “M.” I don’t understand how these stair-stepped children each about four years older than their sibling can all be wearing medium undershirts, but this quirk in the space-time continuum is undeniable.

Carla has very patiently explained that Barron is now wearing an adult medium, Harris is wearing a youth medium and Carlton is wearing a toddler’s medium. See why I am confused?

Perhaps my confusion and irritability over this whole issue is derived from the truth that my children are growing up. Despite the fact that my own father tells me frequently that the time will pass too quickly, it still comes as a surprise when these moments catch me off guard and I realize just how fast their childhoods are evaporating.

All parents go through this, I know, but that realization makes these epiphanies no less unsettling. With every passing day I wonder if I am doing enough to prepare them for what life is going to throw at them. I contemplate what our relationship will be like through their teen years and on into adulthood. I hope and pray that as their innocence transitions into knowing, they will somehow understand that my love is greater than any mistake they could make and my joy is inextricably linked to theirs.

The next time you see me squirming and fidgeting at the neck with one of my T-shirts, just nod knowingly and understand that I’ve once again made an undergarment selection error and I’m coping with parenthood.

At what moments do you realize life is fleeting? What are the circumstances that jolt you with the terrifying realization your children are growing up too fast? If you’ve been down this road, share your wisdom. If you’re going down this road, share your pain. Leave a comment, and we’ll all be better for it.