Adapted from a recent online discussion.

Dear Carolyn:

What if two people work great as partners but not as co-parents?

My husband and I have a fantastic relationship that goes back 15 years, but we cannot seem to get it together when it comes to parenting our 10-year-old son, “Ethan.” We disagree on everything from where Ethan should go to school, to whether it’s okay to spank Ethan (lightly), to how much fast food Ethan can consume in a month before we’re bad parents.

Worse, we feel equally strongly about our opposite viewpoints on just about everything, so nearly once a week we have these knock-down, drag-out fights that lead nowhere, and the choices ultimately fall to Ethan himself.

(Nick Galifianakis for the Washington Post)

It has been suggested that we take parenting classes, but we’re both positive the classes would just confirm our personal stances. Meanwhile Ethan is stuck in a school that’s no one’s first choice, getting away with things right and left because no one wants to resort to discipline without agreeing on it first.

D.C.

Your fighting is worse for Ethan than going to the wrong school plus whatever junk food he eats in a month plus whatever else you’re over-/under-indulging him with as a byproduct of your mutual inability to act like grown-ups.

I won’t include the spanking in that because Ethan is 10 years old. Whatever highly debatable benefits you were (er, one of you was) able to embrace with spanking, you can now achieve by actually talking to the kid.

I also question your “fantastic relationship” assertion. You two aren’t raising Ethan responsibly because your top priority isn’t to love each other or raise him well, it’s to win the argument. Both of you.

Otherwise you both would have realized that selectively bending your rigid beliefs would ultimately be for Ethan’s benefit, even if it meant he was ingesting more fat and salt than you knew was good for him . . . or more fiber and vitamins, in case you’re rigidly in the pro-fast-food camp.

Instead, you’re giving Ethan a wretched model of marriage, of problem-solving, of respectful disagreement between equals — all the while leaving him to his own devices, probably on many of the things you’re dueling over so fiercely.

And now you’re digging in against parenting classes before you’ve even set foot in one?!

This is not the behavior of mature people who work great as partners — it just isn’t. This is how competitors and ideologues behave. And toddlers.

You’re going to have to decide whether you’re in this mess because you’re both stubborn — in which case, see “parenting class,” above — or because you believe letting your husband have his way would actually harm Ethan. In that case it’s time not only to face the irony of Ethan’s childhood gone adrift, but also to consider that the guy you got along with so well 10 years ago had some character problems you failed to take seriously.

If that’s the case, a parenting class is still a great idea — get your butts there, immediately — and a talk with a reputable and talented family therapist wouldn’t be a bad idea, either.

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