05/11/2012 11:27 am ET Updated Jul 11, 2012

What I Know Now That I Am The Mother Of An 18-Year-Old

Two weeks ago, my baby turned 18. The law says he's an adult -- he can vote and sign contracts, and when it comes to his medical and legal privacy the fact that I am his mother gives me absolutely no rights at all. A card came in the mail the other day reminding him to register for the Selective Service. He has already registered to vote.

When his older brother reached these same milestones I wrote "Eighteen is an arbitrary line... It is hardly a finite line...But it is a bright and important one." I was writing proscriptively then -- guessing, assuming, wondering, what it would be like to cross over into a new role for both of us. Now that Alex has gotten here too, I've had a taste of how reality compared to expectation.

Here is what I know:

You are bigger than I am.
And way stronger than I am, and you do a spectacular impression of someone who is ready to face the world -- but every once in a while you will let me see glimpses of the imp with the Dutch boy haircut who needs me.

"Going off to college" is not the dramatic change in our relationship that I thought it would be.
The real Before and After has happened already -- when you got your driver's license last year. I remember the day you learned to crawl -- your utter joy that now YOU had a say in where you went in your world. A car magnifies your independence; I no longer have to factor you into the logistical equation of our day. You now navigate, literally and metaphorically, on your own.

I will not stop worrying about you; I will just have to learn to do a better job of keeping it to myself.
That, in a sentence, is the parenting contract. Since the day you were born I have carried you in my head -- a part of my consciousness always wondering what you are thinking, how you are feeling, where you are. It's not always front and center, but it is always -- will always be -- there.

I thought I was deciding to have a baby 18-years-ago, but now I understand that I was really deciding to have an adult.
An adult who I like as well as love, whose advice I value, whose company I relish, who makes me laugh more deeply than anyone I know.

And that has been the purpose all along, no? Not the first 18 years (which is what all the how-to parenting books are about) but everything that comes after. Not the hands-on part, but the letting go.

When I look at you I will always see past, present and future. The baby that you were, yes. But also the wonder that you now are, and the extraordinary man you will continue to become.