Parents who are having difficulty getting their babies to sleep through the night may be somewhat relieved by a new study showing that a large determinant of an infant's nighttime sleep is simply the luck of the genetic draw.
Researchers in Canada studied sleep records from nearly 1,000 identical and fraternal twins in Quebec, and found that genes largely determine whether children sleep through the night. However, children's ability to nap during the day is controlled more by their environment.
While some parents may find themselves fortunate in having a sound sleeper, the researchers said there are also ways to help a child along.
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