There are many different factors that influence our developing personality, but birth order is one of the more unusual ones. Your place in your family is determined at birth and though blended and even broken families are more common now, for most people that place does not change much throughout their lives. How then, does that impact your developing personality?
Experts suggest that it is a matter of the cues that you receive from your environment and the people around you. The basic characteristics of who you are are set in your earliest years though and if a change in your family position occurs after a certain point, a corresponding change in personality cannot be expected. Similarly, if it occurs before that point, then you personality reveals itself to be much more fluid.
In each family the children are treated differently. In some ways this is because they are individuals in their own right. A good parent treats their child according to their emerging personality after all. The two factors of personality and care are intertwined however, and as you alter the way you treat your child to fit their needs, your child alters the way they behave in order to fit they way they are treated. This is one way to explain the observable effects of birth order.
Another way to explain might be to point out that parents are likely to treat firstborn children certain ways simply because they are first. You might be stricter about following the recommendations of parenting manuals or more careful about your child’s illness. A middle child might get a more lax and confident parenting style or they might get less focused attention due to the increased number of children the family has to care for. The result is that certain family positions are generally associated with certain traits:
Of course, there are documented exceptions to this scenario. There is no all-encompassing system that will tell you exactly how someone will turn out whether your are trying to figure out yourself or your child. One example of an exception is the case of twins. Twins tend to develop the characteristics of either first or lastborn children, but they also develop a clear system of leadership. One twin will be dominant, the other submissive. There are other exceptions as well. All of them point to the conclusion that birth order matters because of the way it affects a child’s family environment, not in and of itself.
Experts have theorized that the traits associated with birth order have developed as a response to the behavior of parents, the behavior of peers, and the behavior of siblings. Presently evidence points towards all three having influence.