Sweig's notion of "parallel play" struck me as a novel insight. Until, that is, I read this
Parallel play is a form of play where children play adjacent to each other, but do not try to influence one another's behavior. Parallel play consists of play that is highly social and contains cooperative interaction. It usually involves two or more children in the same room that are interested in the same toy, each seeing the toy as their own. The children do not play together, but alongside each other simply because they are in the same room. Parallel play is usually first observed in children aged 2-3. An observer will notice that they occasionally see what the other is doing and then modify their play accordingly. The older the children are, the less frequently they engage in this type of play. However, even older preschool children engage in parallel play, an enduring and frequent activity over the preschool years. Additionally, it is sometimes observed in older children when playing video games, particularly hand-held games. In education, parallel play also describes activities where students are divided into pairs or small groups and work on the same activity simultaneously. This gives all students equal opportunity for active involvement and reduces the exposure. (Since all students are playing, none are watching.)
I don't know if this is what Sweig was referring to, or if she was making something up from whole cloth. But, put the US and Brazil in two kids' places, and OUCH!