Knew it.

Here's some more proof that younger siblings are the best siblings.

New research to be published in the journal Pediatrics found that becoming a big brother or sister before first grade may lower kids' risk for obesity.

Researchers at the University of Michigan looked at the BMI and family lives of nearly 700 children across the U.S.

Children who had only older or no siblings by first grade were nearly three times as likely to be obese as their counterparts who did have siblings by then. Children who became older siblings between the ages of two and four were particularly likely to have a healthy BMI by first grade.

"Research suggests that having younger siblings -- compared with having older or no siblings -- is associated with a lower risk of being overweight," study author and developmental and behavioral pediatrician Julie Lumeng said in a news release. "However, we have very little information about how the birth of a sibling may shape obesity risk during childhood."

The authors hypothesize that parents might adjust the way they feed their kids once a new siblings comes into the world. Since previous research tells us that children develop lasting eating habits at an early age, the way they eat after a sibling is born may have an effect.

Even more, kids may engage in additional "active play" and less sedentary time when a baby comes into the picture.

Researchers hope the study sheds light on behaviors parents can learn to create the conditions of a household with two or more children, without actually needing to have two or more children.

"Childhood obesity rates continue to be a great cause of concern," Lumeng said. "If the birth of a sibling changes behaviors within a family in ways that protect against obesity, these may be patterns other families can try to create in their own homes."

Before You Go

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