One evening this past week, my wife informed me that she and I were headed off to do Christmas shopping for our five kids after dinner. I sighed.

It's not so much that I don't want to run out and spend more on luxury items in one evening than we've spent all year. I don't want to, but I've become resigned to this yearly spree, running from store to store, tossing credit cards at sales clerks as if we were identity thieves. No, it's that every year I obsess about making sure that the wealth is distributed as equally as possible among our offspring.

People with only one child don't experience this problem. Only children get all the presents under the tree, every single one. They probably wake up Christmas morning, take one look at all their loot, then do a victory lap around the Christmas tree. With more than one kid, it gets a tad more complicated, balancing values and sales prices to make sure the results are fair and balanced. And with five children in one family, it's like trigonometry.

Kids on Christmas morning have little adding machines keeping a virtual tally in their heads as each gift is opened. As little Bobby Jr. is ripping the wrapping paper off his new football, he's saying "Hey! All right!" But another voice in the back of his head is intoning, "One imitation leather football. Fourteen ninety-nine. Check."

Kids in bigger families aren't doing this to make sure you spent enough money on them (You did. You actually spent way too much, didn't you?). They're doing it to assure themselves that you spent at least as much on them as you did on their siblings.

Just watch when Suzy's new bike is wheeled in from its hiding place in the hall. Suzy's brothers and sisters will start giving each other looks like contestants on "Survivor" planning to form an alliance to knock someone off. Mom and Dad will start feeling queasy, wishing they had a couple other bikes in reserve. I wouldn't be surprised if when Cain did in Abel, it was with a roll of wrapping paper.

I know this because I grew up in a house with lots of brothers and sisters and recall the tension as each child, in turn, unwrapped his or her gifts. It was like a holy holiday and high stakes poker tournament all rolled into one. I distinctly remember Christmas 1969, silently tallying my presents against those of my little brother, assuring myself we were basically even, especially when we both had only one present left.

I opened my last gift to find a LifeSavers "Sweet Story Book," with 10 rolls of Lifesavers arranged in a little cardboard book. Not bad, I thought. Nothing spectacular, but hey, it was candy for a month.

Then I looked over as my brother ripped the paper off his last gift, and my jaw dropped open. He'd gotten "Rock 'Em Sock 'Em Robots." I stared in shock as he jumped up and down, holding aloft the boxing ring with its plastic pugilists, and I made a silent vow to, after a decent interval, knock his block off.

I wasn't all that litigious as a kid, but as I sat there furiously chewing away at chapter one of my pathetic Lifesavers, I seriously thought of grabbing a phone book and seeing if I could get an attorney who would work on Christmas Day.

Thirty-seven years later, walking the aisles of the friendly local super megastore, I was beside myself mentally balancing out the items in our cart, making sure no one child pulled ahead of the others. My wife pointed to a particularly nice, and expensive, electronic item I can't describe (sorry kids, no clues here!) for one of the children. I scanned the other items in the cart. I shook my head. My wife stared at me in frustration.

"It wouldn't be fair to the others!" I said. She sighed.

"Is this about those stupid boxing robots?" she said.

"Fine!" I said. I took the box and put it in the cart, and continued with our shopping. I wonder if the Lifesavers company still make those little Christmas storybooks.

If so, I'm going need four of them.