iStock.com/real444If you're a parent, chances are you've thought about birth order and how it affects your kids. Am I harder on my firstborn? Do my kids have a normal sibling relationship? Does the order in which the kids were born really matter in the long run? Turns out it does. Scientists have done extensive studies on family make-up and how it affects not only how you parent, but your kids' health and personalities.
Wonder if your oldest child is like most firstborns? Here's what science has to say:
1. They go that extra mile for an education. When researchers at the University of Essex's Institute for Social and Economic Research surveyed 3,553 individuals (1,503 groups of siblings), they found that the oldest children in families had a 16 percent greater chance of going to college as compared to their younger siblings.
2. They're born to learn. Is your oldest child a bit of a know-it-all? It could be because of their birth order. Firstborns really are born to learn, according to a 2013 study, published in the Journal of Research in Personality. Researchers at Belgium's Ghent University found that birth order actually affects a child's lifelong goals. The eldest child, they found, wants to "master" or "learn," while the second child tends to want to "win." It certainly goes hand-in-hand with number one, doesn't it? Other studies have also shown firstborns (and only children) tend to pick more academic-oriented careers as compared to their younger siblings.
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3. They may be at risk for diabetes. A study out of New Zealand and published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism claims children who were born first have greater difficulty absorbing sugars into the body and higher daytime blood pressure than kids who were born later in the birth order. And no, it's not because of childhood obesity because ...
4. They're skinnier. That same study that found firstborns are at risk for diabetes also found eldest children tend to be taller and slimmer than their younger siblings. Why? Scientists think it comes down to the mother's uterus -- which changes after her first pregnancy.
5. They get more from Mom and Dad. Think you're equally dividing your time among your kids? Scientists disagree. When Cornell researchers dove into the quality time issue, they found the eldest child receives 20 to 30 more minutes of quality time each day with a parent than a second-born child of the same age from a similar family. Another study at Brigham Young had similar findings -- they estimate firstborns get about 3,000 more hours of quality time with their parents between ages 4 and 13 than the next sibling gets when they pass through the same age range.
6. They're more creative ... sometimes. Still debating the age gap between your kids? This might make up your mind -- when scientists at Washington University in St. Louis studied siblings, they found that firstborn kids tended to be more creative than later-born kids if they had younger siblings of the opposite sex or if their younger siblings were less than three years younger. Not surprisingly, big age differences tend to push oldest kids into parental surrogate roles, while smaller age differences allow for more playtime -- and thus more creativity.
7. They're smarter. Well, their IQs tend to be higher anyway! A study published in the journal, Science, reveals about a two-point gap between firstborn men and men born later in the birth order, with the firstborns coming out ahead. Interestingly, the "oldest sibling" in families where the eldest child died also tended to perform better on the IQ tests.
8. They're bossy ... if they're females. Sorry Sheryl Sandberg, but the science is in, and it turns out some girls are, indeed, bossy. Not only did researchers at the Southern California Child Study Center find bossiness to be more prevalent in firstborns, but they found it to be based on gender, with eldest girls more likely to be domineering than eldest boys.
9. They're more prone to asthma and allergies. Does your eldest child have breathing issues? It might be because of their birth order! According to research presented at the American Thoracic Society's 2008 International Conference, genes act differently in firstborn kids, particularly the genes responsible for asthma and allergies!
10. They have it the hardest. Tougher on your oldest child? You're not alone! When economists from Duke University and Washington University tackled the topic of parental rules and birth order, they found earlier-born siblings are more likely to be subject to strict rules and parental monitoring and more likely to face harsh consequences for wrongdoing than younger siblings.
11. They're less likely to suffer from PTSD. Nobody wants to think about their kids going through a traumatic situation, but have heart. Research out of England's University of Sheffield shows firstborns are less likely than their siblings to suffer from post-traumatic stress disorder. The scientist behind the study isn't quite sure why -- he surmises that younger siblings are more likely to take risks and put themselves in traumatic situations, but it may also be down to parenting style. Other studies have also found firstborns are significantly less susceptible to anxiety or depression.