People who only recently started their families may think they do nothing but give, give, give -- give food, give clean diapers, give smooshy kisses on the back of the baby's little neck and so on -- but in fact, parents and offspring have quintessentially symbiotic relationships.

People who only recently started their families may think they do nothing but give, give, give -- give food, give clean diapers, give smooshy kisses on the back of the baby's little neck and so on -- but in fact, parents and offspring have quintessentially symbiotic relationships.

It's unbalanced at first, of course. Before children can pick up the knowledge that will ultimately be so useful to their elders, they must develop their small motor skills, the ones that allow them to use the muscles in their hands to, say, push buttons.

The first buttons they push will be ours. Most adults have no idea how many buttons they have until their children come along and push them. But that's when the giving back begins. Suddenly we know ourselves much better than we ever did before. We know that we'd rather have the books upright on the shelves than dumped in heaps on the rug. We'd prefer the water stay in the bathtub instead of pouring all over the floor and seeping through the ceiling into the living room. And call us sentimental, but we'd rather the plastic duck be in our child's chubby fist than have it stuck in the S-trap of the toilet pipe.

In a few years, we'll peel back more layers of all the special likes and dislikes that make us us. We don't like lawnmower engines in the living room. We think the gerbil looks cuter inside its cage than it does on the dining room table. And if someone is going to hang out in the doghouse, we'd much rather it be the dog and not our daughter.

This last is exactly my point. Without a toddler daughter to lead the way, I might have lived my entire life without realizing how deeply and sincerely I believe that doghouses are for dogs. Thanks to her decision to crawl inside one day, my self-knowledge base expanded and my life experiences grew exponentially. Because my daughter had tucked herself into a small, contemplative ball in the far corner, I learned what it's like to stick my own head and shoulders inside a dog house. I learned what a doghouse long occupied by a dog smells like. I learned what a daughter who has been in that doghouse smells like when she comes out again. I was positively burgeoning with new knowledge. As adventures go, it could be compared to Neil Armstrong's first steps on the moon.

A few more years, and even as we're teaching our children long division, the difference between states and countries and the reasons we believe slumber parties are the devil's playground, our children continue to stretch our intellects like a bungee cord. They satisfy our own secret curiosity about what's inside the beanbag chair. They teach us that a person really can survive on a diet of rice cakes and granola bars, and they show us how to live as if each day could be our last by holding, and expressing often, the unshakable belief that one more sixth-grade gym class might kill them.

But children teach us more than all this. When they become adults, or almost adults, our children are fonts of knowledge. They tell us what flash drives do. What NFC chips are. The point of hashtags. What Follow Friday is.

They show us where the camera is on our phones. They explain texting. They demonstrate neat apps that leave us round-eyed with awe. They introduce us to people they met on Twitter, just as if we don't feel like we're meeting people they met on Mars.

They give vivid reviews of weird, 3 a.m. cable shows -- shows we will never see because we fall asleep at 9:30. What would we do without children to explain expressions such as ROFL and LMAO? Of course, as soon as the likes of us start spouting these phrases, our children will never use them again, but never mind. As soon as we get wind of new ones, our children will explain those too.

And what did we do for all of this information? Change a few thousand diapers. Lose a few thousand hours of sleep. Oversee a few thousand homework assignments. Almost nothing, in fact. What a deal.

Write to Margo Bartlett at mbartlett@thisweeknews.com.