I'm reading a book on Utopias by Lewis Mumford and he explains that most of the utopias always tried to make sure children weren't too attached to their familie

I'm reading a book on Utopias by Lewis Mumford and he explains that most of the utopias always tried to make sure children weren't too attached to their families. Family can prevent people from pursuing their goals or the skills that they're very good at. The most obvious is example is geography where you can't move to another country.