In happier days, when you were not only still married but still happy with your husband, did you sometimes look at your son and say fondly, “You’re just like your father,” or “You’re so much like your dad”? It was meant as a compliment, and the thought that your son, whether he was then five or 15, was growing up to be like the man you loved sent heart-warmth throughout you.

Now it’s a different story, isn’t it. “You’re just like your dad” is no compliment when it comes from you. Your ex may be otherwise known to you and your friends (although hopefully not to your kids!) as “That #$%$#!” and being like him is not a desirable trait.

You’re walking a road filled with landmines.

• If you tell your son, “You’re just like your dad,” you’re putting into your own mind an emphasis on the similarities between your son and your ex, which may predispose you to negative feelings toward your son.

• If you tell your son, “You’re just like your dad,” and your son knows you harbor antipathy toward your ex, your son may interpret your comparison as a put-down rather than a compliment, even if you were pointing up one of his good attributes and not one of his faults.

• In any case—and even in a happy, intact marriage—even if your son idolizes his father, unless he’s still a pre-schooler, he doesn’t want to grow up to be just like Dad. He wants to be his own person. And you should encourage that.

But our emphasis here is on the pitfalls inherent in telling your son that he’s “just like Dad.” You don’t want him thinking you see in him the same qualities you dislike in your ex. And you don’t want to point out to yourself the ways in which he resembles the man you found it necessary to cut out of your life—or the man who walked out on you and the kids, if those are the circumstances surrounding your divorce.

Even if you notice certain similarities between your son and your ex, don’t dwell on them in your own mind and don’t point them out to your son—and that’s true even if they’re clearly compliments.

You can say, “You know what I love about you? You always  try to see the other fellow’s point of view in a dispute.” You don’t have to say, “You’re just like your dad. He always tried to see the other fellow’s point of view in a dispute too.” You can say, “You’re slow to anger. Something has to get you seriously ticked off before you lose your temper and start yelling. That’s a very admirable trait.” You don’t have to say, “I’m glad you’re slow to anger, like your father.”

This is all the more true if the similarities are negative ones. You don’t have to say, “You’re so darned impatient, just like your dad.” It’s enough to tell the boy he’s too impatient. Leave the comparison out of it. Otherwise, especially if he’s still very young, he may start to worry that you’ll want to kick him out of the family the way you did with his dad, or that you’ll stop loving him just like you stopped loving his dad.

Whoever first said, “Comparisons are odious,” was certainly guilty of over-generalizing, but in this case the statement rings true. Or maybe we should rephrase the saying slightly: “Comparisons are dangerous.”

Curb your impulse to compare your son—positively or negatively—to his dad. You’ll save yourself and your son from a load of potential grief.