Are younger siblings more likely to try growing up too fast?

I notice that the kids who were allowed to wear crop tops in 5th grade, unsupervised iPhones, full makeup and snuck out were more likely to be the youngest. It might not be true though. That particular group were the ones who tried age-inappropriate things. I'm sure there were firstborns and only children involved too. But generally, a lot of them had older siblings. The most "popular" girl back then had three older brothers… Just like most of her friends. Oddly enough, these children often say/think that their parents don't care or know about them doing these things.

I think

In my family, it was the oldest one who tested all the boundaries, and did things too early. But you may be right. Younger kids may resent not being able to do what their older siblings are doing.

In families I knew where there were three kids, it was the middle one who had a hard time behaving well.