According to new research, how mothers and fathers react when their children test their limits may have a lasting effect on their development.
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PROBLEM: Babies like to test their boundaries as they inch toward toddlerhood, and past research has shown that their unruliness during this transition phase can predict they're likelihood of misbehaving in school. How do genetics and parenting styles come into play?

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METHODOLOGY: Researchers led by Oregon State University human development professor Shannon Lipscomb collected data in 10 states from 361 families linked through adoption. They asked the adoptive parents to answer questionnaires when the children involved were nine, 18, and 27 months of age. They also videotaped the kids during temperament trials and the parent-child dyads during structured interaction tasks, and obtained genetic information from the children and their birth parents.
RESULTS: Adoptive parents who overreacted when children tested their patience and made mistakes tended to have kids who act out a lot. Genetics also appeared to play a small role in engendering this kind of behavior, as children raised in low-stress environments but genetically predisposed to such negative emotionality from their birth mothers also had more tantrums than normal for their age.
CONCLUSION: Impatient parents are more likely to have toddlers who get upset easily.
IMPLICATION: The way moms and dads adapt when their children gain more independence and mobility is critical. "Parents' ability to regulate themselves and to remain firm, confident, and not overreact is a key way they can help their children to modify their behavior," said Lipscomb in a statement. "You set the example as a parent in your own emotions and reactions."
SOURCE: The full study, "Negative Emotionality and Externalizing Problems in Toddlerhood: Overreactive Parenting as a Moderator of Genetic Influences," is published in the journal Development and Psychopathology.
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