Elvis Presley sang about a "Blue Christmas," and I'm not feeling so perky myself.

That's not because my Christmas was depressing, far from it. It's that the aftermath was.

We spent Christmas with our extended family back in Elvis's homeland and mine, Mississippi. My four sons spent a little over a week romping through the streets of New Orleans and Biloxi and Ocean Springs with us and, more importantly, running and fishing and playing with their grandparents. The way home was funereal, as all four boys sat quietly contemplating the fact that they were leaving their grandparents behind as we returned home.

I can't say that I understand how they feel.

My grandmother lived right next door, all of my life. My other set of grandparents lived fifteen minutes away, and most of the childhood haunts I took my kids to on this trip (Pirates' Alley, Cafe du Monde, back bay Biloxi) were all places I'd been first with my grandparents. Come to think of it, I can't really identify much of my life that isn't directly affected by my grandparents, especially around the holiday seasons. At Christmas, my late grandfather just ought to be there making oyster stew, and so forth.

Even still, it's a rare day when I don't speak to my grandmother by telephone. I don't think that would be the case if I hadn't spent so much time in her garden picking purple hull pinkeye peas or in the backfields with her harvesting dewberries or riding in her little blue car back and forth to our home-church.

I thought about that as I read this article by Ron Sider in the latest issue of Prism magazine. Sider writes about what's been lost in this mobile and globalizing world we live in, in which most kids don't live near their grandparents. What's being lost, he asks, in a world in which most children only know their families from one generation down?

At the same time, Sider recognizes this is not easily fixed. The western industrialized world has changed from the way almost every previous culture knew it to be: agrarian hamlets with extended tribes working the same land as their fathers and grandfathers.

Sider laments:

"Today, unfortunately, very few children spend that kind of quality time with their grandparents. Often divorce divides families and complicates grandparenting. The mobility of our society separates grandparents and their grandchildren because they live in different parts of the state, country, or world. We all understand the changes in contemporary society that have produced this result. Missionaries have to live in other lands. Specialized educational and professional opportunities seldom pop up next door to our parents' homes."

Still, Sider writes:

"There is a lot to be said in favor of recovering the older model of three-generation families. when grandparents live on the other side of the wall or across the street, they have a wonderful opportunity to support their children and bless their grandchildren. Actually, it is hard to know who is blessed more-grandchild or grandparent. That relationship is certainly more precious than the joys of retiring in Florida or Arizona."

It's a complicated issue. We all know those who move right in next door to "mama and daddy and them" because they haven't initiated the "leave and cleave" responsibility of Gen. 2. And, truthfully, many of those saying "Amen" to this article will be the least functional family structures around: those in which the grandparents are there precisely because they still control their children's lives or because their children are still, well, acting like children.

But that's why Sider, rightly I think, maintains it is not just a scenario in which young families ought to stay put where they are. Sometimes, he maintains, grandparents can move where their grandchildren are. And, in any case, families can plan vacations to revolve not around expensive theme parks but around the extended generations of the family.

Your child would rather know who grandma and grandpa are than how to distinguish Donald Duck from Daffy.

It's worth asking: what are we losing when most of our children can't contemplate going "over the river and through the woods" to grandmother's house?