When a child reacts to an event with laughter and humor, the world around him laughs, too.

For a young child, as with us all, humor arises from the unexpected. When a parent plays peekaboo with a 1-year-old, the disruption of the expected rhythms leads the baby to giggle.

An older child recognizes the context associated with an event. When a parent introduces something out of context, the child smiles and laughs: “That’s not how it’s supposed to be!”

Humor depends on a cognitive capacity to compare and store memories and develop a sense of what usually happens. For a child, the fun of nonsense is the satisfaction she feels in knowing that she can tell the difference between what makes sense and what doesn’t.

Humor can be used to make an intolerable condition tolerable: “You’re teasing me. I can take it. I can laugh.” Whoever is teasing her is then bound to be on her side.

A 3-year-old can already use humor to defuse a parent’s anger about something the child knows she shouldn’t have done. She shows that she recognizes her error, and protects herself from the consequences.

Older children, too, will use humor to disarm their parents, and they can be expected to laugh or become giddy when they know they’ve misbehaved. An adult’s reaction might be, “When you’re silly, I know that what you did wasn’t right. I can laugh with you, but I still can’t let you get away with it. You and I know it was wrong, don’t we?”

Humor and laughter are common forms of communication among siblings and peers at age 3 to 6. In their fantasy play, they use humor to try out and understand the limits of an imaginary situation and to distinguish it from predictable reality.

Children use humor to test the limits of what is real — safely: “Wouldn’t it be funny if I jumped off this table and tried to fly? I’d just plop down and fall on my bum.”

Why do children laugh when someone is hurt? Laughter can be seen as a way to handle the anxiety that another child’s injury sets up: “Will he be OK? What if that happened to me? Maybe it will.”

A parent who understands these anxious feelings can respond to inappropriate laughter with reassurance: “It’s scary to see someone hurt. But laughing won’t help her. We can help her get fixed up and then we’ll all feel better.”

Early recognition of differences in appearance (based on race, gender or disability) can also make children worry that something might change their own bodies. Laughter reduces the anxiety a child may feel about her own fragility.

Laughter isn’t necessarily a mark of insensitivity. Although a child may not be able to admit it, seemingly cruel reactions to differences are more likely a sign of feeling vulnerable. At 5 and 6, children give up their fantasies of being invincible and face how small and relatively defenseless they are.

Children this age also are frightened by their awareness of their aggressive feelings: “Something bad could happen to me for being so mad at Mommy.”

Parents can use humor, just as young children do, to defuse a tense situation. When a small child has pushed parents over the edge, humor can be a safe (but not always readily available) way for them to regain their ground.

WHEN YOU NEED A LAUGH

1. When you’re irritated with a child, use humor to manage your reactions. Thus you bring a fresh perspective to the situation — and model an effective way for your child to handle feelings.

2. Laugh together. A parent who can help an angry child see the humor in her position without making her feel ridiculed is showing her an effective way of calming down. When parent and child can laugh together, they can become close again.

3. Recognize that humor serves many purposes for children and for their parents, too. When a child can laugh at herself, she is demonstrating that she has a strong self-image. Other children like her. Adults feel responsive toward her. Humor can be one of the surest ways of gathering everyone’s support.

Questions or comments should be addressed to Dr. T. Berry Brazelton and Dr. Joshua Sparrow, care of The New York Times Syndicate, 620 Eighth Ave., 5th Floor, New York, N.Y. 10018. Questions may also be sent by e-mail to:

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