Parents often do everything they can to ensure that their children grow up the be the brightest in the class, but a recent study suggests that all their money spent on educational toys and musical lessons may have been spent in vain. According to the research from the University of New Mexico, simply having a happy peaceful marriage is one of the biggest predictors of a child’s overall academic performance in school.

Marital aggression, such as when parents verbally or physically fight with one another, has a trickle-down effect on children, and causes them to be in a state of constant vigilance which ultimately disrupts their sleep patterns. While the odd rough night of sleep may not have many consequences, the research found that children of broken marriages often suffer from chronic sleep troubles that led them to wake up multiple times through the night.

"They become vigilant at detecting a level of threat," said Ryan Kelly, one of the researchers involved in the study, in a recent statement. "The child starts to worry about a particular parent, their own personal safety or the safety of their siblings. These specific worries are what interrupts the child's ability to sleep."

Poor sleep seems to have the biggest impact on a child’s academic performance, causing children to perform poorly on standardized tests and get lower grades. In addition, poor rest caused by family stress seemed to have an effect on the children’s physical health, resulting in symptoms of depression, anxiety, and increased body mass index (BMI).

Unfortunately, the damage of a troubled childhood seems to be long-lasting, and the team noted that children who were exposed to family stress at age nine still continued to experience sleep problems at age fifteen. Thankfully, it does seem to be reversible.

"There are interventions that parents can do to decrease family stress ultimately protecting the sleep of their children,” explained Kelly. “Parents need to know arguing in harsh ways disrupts the development of their children. Heavy alcohol use is also discouraged because it can make a child feel unsafe."

Source: Kelly RJ, El-Sheikh M. Parental problem drinking and children's sleep: The role of ethnicity and socioeconomic status. Journal of Family Psychology . 2016

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