This week, I'd like to examine one of the common English expressions uttered by young Homo sapiens, but then usually abandoned as they reach maturity.

This common expression is typically uttered when the specimen seems to be undergoing stress, based on the volume of the vocalization.

"But that's not fair!" is a short expression, but one with many nuances and meanings.

This utterance is often accompanied by agitated behavior, such as stamping of the feet and wild movements of the eyes and hair.

Typical lines preceding this one include: "I did the dishes yesterday, so it's not my turn," and "I was only 15 minutes late, and it wasn't my fault."

When I first became a parent, I tended to ponder the question, and ask myself whether or not my pronouncement or judgment that evoked this expression really was fair.

Then I got old and lost my patience. My youthful ones, as they grew into teenagers, became more skillful at arguing every point, no matter how trivial, no matter that they could have accomplished whatever task I'd assigned them in a fraction of the time it took for the argument that ensued.

The good news is, all this practice at argument could someday prove useful to my children, if they should become lawyers, con artists or newspaper reporters.

The bad news is, eventually all parents learn there's no way to win an argument based on fairness, due to the painful reality there is no Parental Supreme Court that will hand down a ruling to your child that he or she will accept with grace.

Actually, when I was a kid, there was a Parental Supreme Court, also known as my father. All decisions were appealed to my dad and his word was law.

I'd like to think that I had the same authority with my children, but that does require nerves of steel and the constant certitude that you are always right, which I never had, and now have even less as a mom.

However, to trot out a cliche, age has its privileges. And one of the nice things about being a Really Old Mom is you can just ignore all the rules and do what you like.

When Curly Girl utters those fateful words: "That's not fair because you don't treat my brother like that," I no longer ponder the question. I just ask her if she's a 16-year-old boy who runs track and plays football.

If the answer is no, then I guess she's not identical to her brother, so I don't have to treat them the same. I repeat this sentence an hour later, when her brother comes to complain about how I constantly favor his sister over him.

Then there are the times they both come at me complaining of unfair treatment at the same time. I keep waiting for Buddy the Wonder Dog to chime in, too, griping maybe that he doesn't get walked as much as the pooch next door.

Nowadays, I have the same answer, the one that my parents used to give me. Only now, it doesn't irritate me so much.

"Not fair? Well, life isn't fair. Get over it."

I've discovered with glee that it's a lot more fun to say those lines than to hear them. And I expect someday to hear them again, coming out of my kids' mouths.

Marla Jo Fisher was a workaholic before she adopted two foster kids several years ago. Now she juggles work and single parenting, while being exhorted from everywhere to be thinner, smarter, sexier, healthier, more frugal, a better mom, better dressed and a tidier housekeeper. Contact her at mfisher@ocregister.com. Follow her on Facebook at https://www.facebook.com/FrumpyMiddleagedMom and on Twitter @FrumpyMom.

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