Birth order has no effect on children
Whether your child is a firstborn or the youngest, it actually has no real effect on their personality or intelligence.
Nearly 400,000 children took party in the University of Illinois study and, although the study found that firstborns are on average more intelligent than children born later, the difference between them was actually so small it is practically irrelevant.
Generally firstborns had only one IQ point higher than their younger siblings, which, in real life, is meaningless. Although the eldest siblings were on generally more extroverted, it was only by the smallest amount, which would be completely unnoticable in a real-life situation.
So if you were worried about the effect of being a younger or middle child could have on your children, or whether you should treat your children differently based on their birth order – never fear!