Today's topic is inspired by the talking with my sister.
We come from a city in the south of China, where it's common a family has more than two children of similar ages. Since people are making a living away from hometown, they keep strong connections for business cooperation and next generations' marriage locally.
That's the reason why my sister and I have chances to know many multi-children families (born from the 1970s to 2000s). And we have an interesting unofficially finding: children's characters vary in different families, but in one family, there is a common law of children's characters distribution, which is caused by parents' common demand.
Parents' common demand could be divided into external and internal. The external is to show, while the internal is to control. As for being parents, the former lets them enjoy vanity, the latter makes them enjoy the authority.
That's why the firstborn (girl) and lastborn (boy) have high odd to be confident and emotional, because of the external requirements. Most of them seem to free for adventures compared to the middleborn children, but they have a too high dependency on social attention and marry in an earlier age to start another parent-children cycle.
For the middleborn children (girls), they balance the relationship between the parents and children to meet the internal needs, they deal with the shadow of the bright picture of a happy family, so they priority stability than adventures. Negatively, most of them seem to be more mature, but find it hard to please self.
To conclude, when parents shape children's characters based their requirements unconsciously, no matter it's a confident, hardworking, positive child, or an uncaring, lazy, negative child, he or she can't draw a clear line between others' expectations and their true need.