Birth order——does it matter? Are you different because you are the first, second, or third child in your family—or maybe the last of nine?

A study found that first-borns have an average IQ that is three point s higher than people who fall into a different place in the birth order, perhaps because first-borns often help younger brothers and sisters, which improves their own skills. In 2007, an international organization of CEOs found that 43% of CEOs are first-borns,33% are middle children, and 23% are last-borns. First-borns are more likely to be doctors and astronauts and get higher pay.

If first-borns are more successful, last-borns are generally more agreeable(讨人喜欢的).They are also more likely to be funny, possibly to get attention from all the bigger people at the dinner table. Mark Twain and Stephen Colbert are both the youngest in large families, and Jim Carrey is the youngest of four. According to a 2007 Time magazine article, "The Power of Birth Order", last-borns are more likely to be artists and successful businessmen.

Then there are the middle children:We have not ignored(忽视) them! Many middle children are short of one on one time with their parents. They often feel  short changed:The oldest gets more rights, and the youngest is spoiled(宠坏的). Though they may be ignored, middle children are more likely to grow into easy-going adults.

Many factors(因素) make us who we are, but if the research is correct, birth order may be one of the most important factors.