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"A child's position in the family impacts his personality, his behavior, his learning," expert says.
Ah, sibling rivalry. Relentless competitions, name-calling, hair pulling and blame shifting plague households with two or more children everywhere. Can't we all just get along?
Well, sure, sometimes. But the reality is that all siblings aren't created equal and they don't get treated as such.
Firstborns, for example, often get shafted because parents are stricter with them, while later-born kids might have fewer rules. Everyone knows that the youngest seems to get away with murder because parents have seen it all before. And where's the middle child in all of this? Forgotten or overlooked.
Depending on birth position, there are special roles within families, leading to different adaptation patterns and different personalities, says Ben Dattner, a New York City-based organizational psychologist.
As a result of a stricter upbringing, for example, firstborn children tend to be more extroverted and confident, while second-born kids are more rebellious and open to new experiences, he says. The youngest child is usually the most creative and can be manipulative to get his or her way.
Clearly, birth order affects personality, but what about career advancement and success? Several studies show that firstborns and only children usually reach higher educational goals, obtain greater prestige and acquire more net worth, while the middle child is likely to struggle a bit more.
"A child's position in the family impacts his personality, his behavior, his learning and ultimately, his earning power," says Michael Grose, author of "Why Firstborns Rule the World and Last Borns Want to Change It."
"Most people have an intuitive knowledge that birth order somehow has an impact on development, but they underestimate how far-reaching and just how significant that impact is. "
Here's a look at the effect birth order may have on you:
Personality: Firstborns are ambitious, assertive, dominant and disciplined compared to their younger siblings. They're determined to succeed yet fearful of losing position and rank, and are defensive about errors and mistakes, Dattner says.
Compensation: A recent survey by CareerBuilder.com found that workers who were the firstborn child in their families were more likely to earn $100,000 or more annually compared to their siblings.
Professions: The oldest tend to pursue vocations that require higher education, like medicine, engineering or law. Firstborns from the CareerBuilder.com survey reported working in jobs in government, engineering, pharmacy and science. Ohio State University researchers found firstborn children were more likely to pursue "intellectual" jobs.
Job level: Workers who are firstborn are more likely to report holding a vice president or senior management position, according to the survey.
Famous firstborns: Oprah, Hillary Clinton, Winston Churchill, Sylvester Stallone and Bill Clinton.
Personality: Middle children are good at negotiation, peacemaking and compromise, Dattner says. They are easy-going, diplomatic and are usually closer to friends than family.
Compensation: More middle children identified themselves as earning $35,000 or less per year than firstborn or youngest children, according to the CareerBuilder.com survey.
Professions: Middles tend to have excellent negotiating and people skills -- anything that employs these skills is a great fit. Middle children from the CareerBuilder.com survey said they work in nursing, law enforcement, firefighting and machine operation.
Job level: Middle children were more likely to identify with professional and technical staff level positions in the CareerBuilder.com survey. They also reported being the most satisfied with their current positions.
Famous middles: David Letterman, Richard Nixon, Madonna and Princess Diana.
Personality: Youngest children love the limelight and are used to sitting in it. They are charming, creative, have a good sense of humor and manipulate others when they want to get their way.
Compensation: Last borns were the least likely to report earning six figures, according to the CareerBuilder.com survey.
Professions: Youngest children often gravitate toward artistic and outdoor jobs, according to the OSU survey. They're also successful in journalism, advertising, sales and athletics. Those who responded to the CareerBuilder.com survey reported working in art, design, sales and information technology.
Job level: The majority of last borns in the CareerBuilder.com survey held administrative and clerical level positions. They also reported being the least satisfied in their current jobs.
Famous younglings: Jim Carrey, Billy Crystal, Steve Martin, Cameron Diaz and Rosie O'Donnell.
Personality: Only children are similar to firstborns in that they are motivated to conform to parental expectations, Dattner says. They are also achievement-oriented, successful in school and have problems delegating work. Research shows they are more confident, articulate and imaginative than other children. They also hate criticism and tend to be perfectionists.
Famous only children: Jack Welch, Tiger Woods, Alan Greenspan and Maria Sharapova.
Personality: Because of their equal status in terms of age and genes, twins are usually treated the same and turn out similarly. They tend to have different personalities and interests, but are closer to each other than other siblings and tend to have less conflict with each other than other siblings, Dattner says.
Famous twins: Abigail and Esther Friedman ("Dear Abby" and "Ann Landers"); Mary-Kate and Ashley Olsen; Joel and Benji Madden; and Jenna and Barbara Bush.
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