When children swear, what should parents do?

They curse. More than we'd like to acknowledge and at younger ages than we'd like to think possible. Consider this: Tots between ages 3 and 4 have a lexicon of 35 to 39 swearwords, and the girls outswear boys at that age, according to one recent study. Don't I know it?

My children and I were playing one Saturday when my daughter spilled a cup of water in our hallway. A shocking expletive came out of her mouth. Then she repeated it.

I don't know what was more stunning — that my sweet little 2 1/2-year-old had uttered those words, breaking the Second Commandment in the process, or that she had said the phrase in context.

I was horrified. And I didn't have to ask where she had learned it. (To the confessional, I go.)

Cursing, swearwords, expletives — whatever you want to call them — are an expected aspect of growing up, some experts even argue a healthy one, but why children and teens curse varies with age, as does how parents can and should respond.

Timothy Jay, a psychology professor at Massachusetts College of Liberal Arts, has been studying children's swearing for more than 30 years and presented the findings of his latest research this fall at the Sociolinguistics Symposium in England.

While children aren't swearing more often than in the 1980s, Jay's research shows, they are picking up dirtier words, and earlier.

Gender differences also were notable. At preschool ages, boys and girls have a similar swearing repertoire, but boys begin swearing more frequently, more offensively and more creatively as they age.

"Before kids go to school, they know all the words you aren't allowed to say on television," Jay said in a phone interview from his home.

Watch what you say

Young children might swear because they're simply repeating words they've heard a parent, adult or older child use, said Lyla Tyler, a licensed marriage and family therapist who specializes in children and families in Sacramento.

They're also picking up on the tone with which the word is used.

"They think 'That must be a special word' so they throw it out there," Tyler said.

By elementary school, children know what swearwords are and use them as a way to imitate older children and experiment with boundaries.

Cindy and Paul Ainger's fifth-grader began swearing a few months ago. Their child, who's in the Gifted and Talented Education program, seems to view dropping the s-word and d-word as a rite of passage, Cindy Ainger said.

"She says 'I'm not a baby anymore. I should be able to talk the way I want to talk,' " Ainger said.

They've been able to quell their daughter's cursing around her younger brother and older relatives, but squashing it completely hasn't yet worked.

"I tried doing the swearing jar, and she's not responding to that at all," Ainger said. "I don't know how else to make her stop."

Jay, the Massachusetts professor, wrote "What to Do When Your Kids Talk Dirty" (Resource Publications, $15.95, 148 pages). He said one way to tackle foul words is to help the child understand the three R's — reason, respect and responsibility.

"Think about how you use your language, be respectful of others, and if you transgress, you're responsible," he said.

Growing independence

For teenagers, conversational cursing abounds in person, in text messages, in tweets and on Facebook.

Connie Yu, 15, said swearing is pretty common among her friends at Franklin High School, and she admits swearing when she feels frustrated or angry.

Yu never curses around her teachers or family, however.

"I would get in trouble," she said.

For teens, cursing is a way to express frustration, much like an adult does, and a way to conform to the pressures they face within teen culture.

Parents should recognize cursing as a sign of growing independence and explain to the teen where they stand on profanity. Is it acceptable in certain situations and not others?

Parents also should tell teens that other people's opinions of them is determined by the language they use, said Robert Epstein, a San Diego psychologist and author of "Teen 2.0: Saving Our Children and Families From the Torment of Adolescence" (Linden Publishing, $18.95, 500 pages).

"Good parenting amounts to nurturing competence," he said.

Kathy Correia, a Sacramento mother of two boys, said it's pretty rare to hear her 14-year-old or 10-year-old swearing —"It's not a matter of course, but they might say it if they think you're not listening," she said — but when an opportunity arose recently to talk to her elder son about cursing and using God's name inappropriately, she took it.

"There are a lot of other ways to say you're unhappy," she said.

The best thing a parent can do if a child curses, either at you or otherwise, is stay calm. That's something Epstein, a father of six, understands all too well.

Epstein's oldest son was 4 years old when he started experimenting with swearwords. Epstein and his wife had talked to their boy about the ability to upset someone with such words and that "you have to be careful when you say these words," he said.

One day, the family was at a picnic when they heard their son screaming. When the parents ran to the boy, who was sitting forlornly on the ground, he told them his 2-year-old brother had just peed in his face.

He asked if this was the right time to use a particularly bad swearword.

"I looked at him and said 'Yes, this is the right time,' " Epstein said.

Offensive as the words may have been, they were a sign of growing independence and maturity, Epstein said.

"It was a very poignant reminder that under certain circumstances, we accept profanity as appropriate and as an expression of intense emotion and intense anger," he said.

Even if it comes from a person too young to know better.