(1) Inundating them w/responsibilities FAR BEYOND their level.
(2) Viewing & treating them as proto-adults instead of seeing & treating them as THE CHILDREN they are.
(3) Forcing them to be parents to younger siblings, it is THE PARENTS' job to raise children, NOT THE OLDEST CHILD!
(4) Expecting them to be the example-setters in the family. Again, it is THE PARENTS' job to set the example for the family, NOT THE OLDEST CHILD!
(5) Not spending as much time w/them as you do your younger children. Oldest children need time w/their parents. However, parents oftentimes fail to realize this, believing that oldest children do not really need them. This explain why oldest children are jealous of, even hating their younger siblings because parents spend very little, if no time with the former.
(6) Not giving them individualized attention & love. Parents of oldest children often feel that their oldest do not need as much individualized attention & love because they are "big boys" or "big girls" and being such they are "too old" for such.
(7) Treating them as they are disposable. Oldest children are oftentimes dethroned, if not discarded or disposed in favor of younger siblings. That negatively impacts upon an oldest child's self-esteem. Many oldest children are needy as adults because of this dethronement. They are also envious, even spiteful of their youngest siblings because of this. This neediness & spitefulness goes into their future relationships w/peers, friends, spouses, & even children. They may become bullies towards others because of the slights they experienced at the hands of their parents as children.
(8) Putting their needs last. Parents seldom consider the interests & needs of their oldest children. They are oftentimes put on the proverbial backburner in favor of the interests & needs of the younger siblings. Oldest children learn early that their interests & needs do not count at all. As a result, they either become self-abnegation or exhibit strong braggadocio-asserting their abilities at every turn, even downgrading & criticizing others to elevate themselves.
(9) Giving them adult responsibilities & roles in childhood.Children are supposed to be children, enjoying an unencumbered childhood.There is ENOUGH time to become an adult. Let your oldest child.....be a....CHILD.
(10) Blaming them for things their younger siblings do.This is tantamount to child abuse.It is beyond child abuse, it is EGREGIOUS behavior on part of the parents.