It goes on sale next month. A new study out today stirring up an age old debate about siblings. Were you and your brothers and sisters treated the same by mom and dad? Is it entirely different to be... See More
It goes on sale next month. A new study out today stirring up an age old debate about siblings. Were you and your brothers and sisters treated the same by mom and dad? Is it entirely different to be the oldest or the youngest? Onto two economists say they have unlocked answer and you really can see the answer later in life. Here's abc's lindsay davis. Marcia, marcia, marcia. I'm in her shadow all the time. Reporter: Jan brady may have been onto something. Based on research firstborns tend to get the best parenting and the best grades. According to the data, the explanation is simple. Parents are more strict on older children and tend to give them more attention. The new reason for siblings rivalry. I think that's true. I'm smarter. I'm the last. Reporter: Internet studies have suggested firstborns score on average three points higher than iq tests. They've got 100 percent of parental attention. Reporter: Look at the most recent presidents, five of the last seven all oldest children. Need more proof? 21 of the first 23 astronauts were firstborns. Firstborns like instein won noble prize. Even joan of arc all younger children, bragging rights for all the younger siblings out there like me. Linsey davis, abc news, new york. This younger sibling is right there with you, lindsey.
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