A news study has revealed that children learn to use profanities and expletive language at about the same time they begin speaking these days.
Researchers also found that children are swearing more often than children did just a few decades ago.
Timothy Jay, a psychology professor at Massachusetts College of Liberal Arts, suggested that the rise in profanity among children is not surprising, given the general rise of the use of swearing among adults during the same time period.
"By the time kids go to school now, they're saying all the words that we try to protect them from on television. We find their swearing really takes off between (ages) three and four," Live Science quoted Jay as saying.
Kids aren't learning swearing at an earlier age from the television they watch. Instead this rise in cursing mirrors the rise in cursing among adults in the past thirty years.
It may not help that parents can sometimes be hypocritical when it comes to swearing.
Nearly two-thirds of the adults surveyed that had rules about their children swearing at home found they broke their own rules on a regular basis. This sends children a mixed, confusing message about swearing and when it's appropriate.
Previous research into swearing has shown it has a significant impact with problems at home, in school, and at the workplace.
The frequency of swearing has traditionally peaked around a person's teenage years, and declines thereafter.
However, the new data presented suggests that swearing is occurring at a younger age, suggesting that the peak may also move to younger children over time.
Children do not appear to be yet using worse swear words than in the past - just common swear words more often, according to the new research. Although there are over 70 different common taboo swear words in the English language (some of which also vary from English-speaking country to country), 10 frequently used words account for over 80 percent of common swearing - fuck, shit, hell, damn, goddamn, Jesus Christ, ass, oh my god, bitch and sucks.
"As soon as kids can speak, they're using swear words. That doesn't mean they know what adults know, but they do repeat the words they hear," said Jay.
The study was presented at the Sociolinguistics Symposium.