The other day, I read about some really cool research that suggests that little kids are naturally altruistic.

It got me thinking: What is it we do that stops them from being that way? Because, let’s face it, not all big kids — and definitely not all grownups — are kind and look out for others.

Felix Warneken, a Harvard researcher, studies the evolutionary origins of human cooperation. For years, people have thought that selfishness is the norm and that parents and teachers are the ones that teach children to help. Warneken wondered if this was really true, and did a bunch of experiments with young children to test their altruism.

He and other researchers did things like drop things in front of kids (playacting that it was an accident) and see if they picked them up — and the kids did. If the researchers dropped them clearly on purpose, the kids didn’t pick them up. In other experiments, the researchers pretended to have trouble doing something — like getting something out of a box — and toddlers routinely came and helped, even when they had a fun toy to play with instead. When the researchers added rewards, they found that rewards didn’t make kids more likely to help — in fact, they found that after a while, the kids who got rewards lost interest in them and stopped helping, whereas the kids who didn’t get rewards kept right on helping.

So interesting — and so hopeful. Until you realize, like I said before, that not all kids stay kind and helpful.

It seems to me that there are three likely contributors to this problem:

1. There’s not a lot of positive reinforcement for altruism. I mean, most of us would thank our kids for picking something up when we dropped it or for holding a door. But I don’t know that we all would make a big deal out of it. We might be pleased, or pat ourselves on the back for the really excellent parenting that produced such a nice kid, but I doubt that most parents make a point of actively encouraging altruistic behavior. On the other hand, we do go out of our way to actively encourage achievement. Which leads me to the second likely contributor …

2. There is a lot of reinforcement for behavior that isn’t altruistic. When’s the last time you saw a parent praise a child for letting the other team score a goal? Or the last time a you heard one praise a child for helping someone instead of studying for a test? Let’s face it: As a society, we may say we value kindness, but we value achievement more. That’s what a kid is going to get kudos for — and it’s hard to achieve and be truly altruistic at the same time.

The biggest contributor, though, may be this one:

3. There’s not a lot of role-modeling of altruism. It’s the inconvenient truth of parenthood: Kids pay more attention to what we do than what we say. So we can talk all we want about being kind and helpful, but it’s our actions that matter. Picture this: A child is walking with his mother, and a passerby drops a glove. The mother notices but is in a hurry so doesn’t pick it up. The child goes to pick it up and is pulled along by mother. What’s the lesson learned?

We all let so many opportunities for kindness pass by. We don’t always stop to pick up dropped gloves, hold doors, help cheer up crying children, feed expired parking meters, donate to whoever is collecting for a cause or club outside the grocery store, help carry heavy packages or dig into our wallets when the person in front of us in line comes up a little short. How many of these things happen with our children watching?

And those are just the little things. Bigger acts of charity are even less common — and so even less likely for children to see.

It’s so sad. Because, really, this research suggests that it’s not so much that we need to teach our children to be kind — we just need to get out of their way, and not stop them.

Reading the article made me do some serious soul-searching about myself and my parenting and all the chances I might have missed.

It’s worth thinking about. If all of us parents could try not to let those opportunities to help and care pass by, if we could all try being kinder, if we could just try not to squash the kindness in our kids, just imagine what might happen.

And maybe, if we switched things around and followed their example, we could be kinder too.

Claire McCarthy is a pediatrician at Boston Children’s Hospital. She blogs at the Huffington Post, where this article originally appeared, and at Boston.com as MD Mama.

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