But the debate over the impact of birth order gained new urgency this summer when the results of a new study were announced: Firstborns' IQs tend to be higher than those of their younger siblings.

Does that mean later-born kids are destined to be less accomplished and successful? Studies like this don't tell the whole story -- and neither do birth-order stereotypes. Here's how to bring out the best in each child:

Norwegian scientists analyzed test results and birth data from more than 241,000 military conscripts and found that oldest children had an average IQ of 103, second children came in at 101, and third-borns were at 100.

Will this scenario play out in your family? Not so fast. Like all studies, this one has limitations:

• The study's Norwegian -- maybe there's something special in the lingonberries over there.

• The subjects were all male -- who knows if it's true for sisters?