I concur with everything everyone in comments here has said. LW sounds like an issue, and she should've contacted the mom who decided to scold everyone to discuss matters... and maybe should've talked to Liz about why she felt singled out (did she do some of the things mentioned? did the mom point at her and say, "you terrible child have been bullying my darling!"? does she just kind of generally assume that she's being especially scolded in any situation?)

Neighbor kids are, by and large, useless baggage anyway, in my experience. It's the kids at school who are likely to stick with Liz -- neighbors come and go. Are the neighbor kids part of the school scene? Is it likely to spill over? Or is school where Liz feels safe to say, "My mom overreacts to things all the time, I'm sorry."?