I WOULD NOT want to be the oldest child in a medium large to very large family (5 and more children per household). Oldest children in the family are seen and expected to be the more responsible and mature one. They are THE LEAST CHILDLIKE of all siblings. They must be as near perfect as possible. They must also be on their VERY BEST behavior. They are held to higher and more stringent standards than their younger siblings. They are the example setters and standard bearers for younger siblings.
Oldest children in small and medium sized families (2-4 children per household) are in a more glamorous position regarding their ordinal birth order. They are seen and treated as the hip and/or cool older siblings whom the younger siblings want to emulate. Although they are placed in responsible and authoritative positions, they do have a normative childhood and adolescence.
Oldest children are expected to be protoadults early in life. However, oldest children in medium large to very large families, the word protoadult has a very negative connotation. The position of oldest children in such families are akin to forced laborers and enslaved persons. They must be ON 24/7/365 for their parents and younger siblings. They have NO individual lives of their owns, as their needs are subverted for the good of parents and younger siblings.
Oldest children in such families are inculcated to place THEIR needs last. They are THE TRUE PARENTS/CARETAKERS of the family, not the parents. In fact, they are PARENTIFIED children whose normative and formative years are akin to the winter solstice. Oldest children in medium large to very large families have it THE HARDEST. They do not indulge in the things that oldest children from small and medium size families indulge in. Also, oldest children in medium large to very large families are THE LEAST likely to obtain an education as they are needed to work to supplement family income.
Oldest children in medium large to very large families are often CAST ASIDE by their parents when they are not servicable commodities to their families. Middle children in medium large to very large families are OFTENTIMES IGNORED. Well, oldest children in such families are IGNORED by their parents when they do not serve their parents' utilitarian purposes. Oldest children in medium large to very large families are THE SECOND MOST NEGLECTED children as more parental time is SPENT on younger children.