"Meet you in 45 minutes," the 16-year-old boy said, giving a wave as he disappeared into the lively Christmas throng at the suburban mall.

I watched for a moment as the crowd swallowed him, and I was struck by the awareness that, to the world, he would look like just another teenage boy in jeans and a hooded sweatshirt. Whereas to me -- well, no points for guessing what a boy means to his mother. A Ming vase is a bagatelle, a cheap party favor, compared with a child.

"We're going to take the escalator," one of the middle girls was saying, meanwhile. "Don't worry, we'll stick together."

"Yes, I have my phone," said the other. "We'll meet you back here on time."

"OK, have fun!"

"We will!" With happy smiles, they turned to make their way down the gleaming hallways and through the clouds of scent that hang like fog around cosmetics counters and stores for fashionable adolescents.

Between huge racks of sparkly evening dresses ("40% Off!"), their heads bobbed into sight for a moment -- one bright blond, the other a darker blond -- before they, too, receded from view.

"Everyone is getting so grown up," said the children's grandmother.

"Even me," said the youngest child.

"Especially you," my mother said warmly.

I was still gazing a bit vacantly across the store in the direction the girls had gone. As with their brother, watching them disappear into a mob of strangers brought a strange pang on this last-minute dash for Christmas gifts. I felt a fresh consciousness of the fact that although a crowd may seem anonymous -- faceless, even -- it isn't. A crowd is actually made up of specific, distinct, particular, idiosyncratic individuals who are precious and irreplaceable to the people who love them.

My mother sighed. "Looking at all this," she said quietly, gesturing to the heaps of marked-down sweaters, piles of boxed bottles of cologne and mannequins in sheath dresses, "I can't stop thinking about Newtown."

So it wasn't just me.

"Everyone is out shopping for Christmas presents," she went on, "and there's nothing wrong with that. But I keep thinking that what really matters is Christmas presence."

"Oh, that is so true -- "

"Yes it is!" interrupted the smallest child. "So let's go get some Christmas presents!"

We laughed, and it broke the moment of sober contemplation. The three of us joined hands and set off -- but I have to admit that my heart wasn't really in it.

Oh, I was happy to help my daughter find small gifts for the rest of the family. It was charming to conspire with her in deciding whether a sister would prefer woolly slippers or a shiny bracelet, whether her brother would like a calendar or a stick-on mustache.

But since last Friday, the trinkets and gifts we've acquired have lost whatever gauzy semblance of "holiday magic" they may ever have had. This Christmas, they'll be wrapped up and waiting under the boughs of a beautiful Christmas tree and, as my mother said, "there's nothing wrong with that."

Come Boxing Day, though, these presents will still be what they always were: stuff. It's not the presents that count, and not even the thought behind them. What matters is the presence of those we love. It is the most substantial gift we can give each other.

Meghan Cox Gurdon's column appears on Sunday and Thursday. She can be contacted at mgurdon@washingtonexaminer.com.