Yep.. even i also agree..Younger kids are more smarter.. they tend to learn from mistakes what elder has done..they also try to get the edge in the family by not committing the mistakes done by elder ones..in younger ones especially two brothers or two sisters, younger ones are less emotional and they mark the behavior of the people more accurately and act fast towards what should be the reply..Elder ones are more emotional they try to take things lightly & casually as compared to younger ones. In India most of the times younger ones have less responsibility of family & social & therefore they have no additional burden over their mind and hence they use that part of mind more actively.