Why do babies hit the people they love most?

The full narration of the video.

A stranger holds him: calm as can be. You pick him up: smack. Mealtime too: the spoon goes, the bowl goes. You pick it up. He throws it again. Is he turning bad? Or does he just not like you?

Start with a survey. US researchers asked four hundred seventy-seven mothers. Of babies six months to two years old, ninety-four in a hundred had lashed out in the past month. Hitting and throwing peak at around eighteen months.

When nearly every baby does it, it isn't turning bad. So what is he doing? First: he has something to say, and his mouth can't keep up. At eighteen months, many babies know only a handful of words.

So his hand works like a car horn. One honk can mean move over, look at me, or just hi. A smack is the same: I'm mad, play with me, I'm too excited.

Second: this little car doesn't have its brakes yet. The part of the brain that holds the hand back sits behind the forehead, and it grows slowest. Experts say kids only start learning to hold back around three and a half to four.

Yet in one survey, more than half of parents expected it before age three. So he can say no hitting, and the next second, the hand flies again. Throwing is something else.

He's running an experiment: let go, where does it go? Does it make a sound? Will you pick it up? Every throw teaches him a little more: things fall, they're still there, and you come back. So why you, of all people?

One reason is simple: you spend the most time with him. You're the one within reach. The other comes from many pediatricians and psychologists. Out in the world, he holds it together. Back with the person he trusts most, the bad mood finally comes out.

There isn't much research on this one yet. But think of it this way: that smack means he doesn't treat you like a stranger. So what do you do? Gently hold his hand and calmly say: no hitting.

Then put it into words for him: you're mad, huh? You can stomp, you can hit the pillow. Don't hit back. He learns from what you do, not what you say. After three, most kids hit less and less. If it keeps getting worse, ask a pediatrician.

Grown-ups do it too: hold it in all day, then snap at the people closest to us. When your little one hits, is it more often anger, or too much excitement?