When they are 2 years old, children who are behind on vocabulary and other measurable language development milestones do tend to display more behavioral problems than their more verbal peers. But over time--the children in the study were followed until they reached age 17--those issues disappeared, and the kids showed no increased behavioral or emotional delays or problems as long as other development was normal.
The study's authors attribute the early behavioral issues to the children feeling frustrated at their inability to express themselves and be understood. "When the late-talking children catch up to normal language milestones, which the majority of children do, the behavioral and emotional problems are no longer apparent," the paper's lead author, Andrew J. O. Whitehouse of the Telethon Institute for Child Health Research in Perth, Australia told The New York Times.
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