Introduction As each child is born, they enter into a different environment than the previous child. Because parents are more experienced upon arrival of a second child, they may be calmer, yet now, the children need to compete for their parents attention and resources (Zanjonc 2001). According to the 2004 government census (http://factfinder.census.gov) the average family size in the United States in 2004 was 3.18. Therefore, in most families, there is a first born, middle child and last born. The different environments these successive children are born into may affect them in different ways. The ways in which birth order and family size can effect the development of a child has been studied in many ways. Researchers have looked for a link between birth order and a number of human conditions, from intelligence and personality to homosexuality (Bogaert 2002), risk of cancer (Brown 2001) and sports anxiety (Flowers and Brown 2002). Researchers have even looked for a connection between birth order and the chances of a child having an imaginary friend (Bouldin and Pratt 1999)