Also anecdotal but I was the first child of young parents with no siblings, cousins, or children of parents' friends around for a lot of my life. When other kid

Also anecdotal but I was the first child of young parents with no siblings, cousins, or children of parents' friends around for a lot of my life. When other kids did come along in our social circle they were much younger so I spent a lot of time socializing with the adults instead. I had to consciously context-switch my behavior to a huuuuuuge degree whenever I spent time with my friends at school and such because acting the way I did in a lot of my life outside school just didn't work. Nobody would have understood how to relate to me. I've always been very social and never had any anxiety around it but I still had to put in some work to act normally around other kids/teenagers after spending so much time with adults. And I went to a normal public school and did a zillion activities with other kids!