Halloween is honestly probably one of the easiest nights of the year to abduct children. Everyone is in costume, kids are often unattended because they are walking around neighborhoods they are familiar with. 

La Llorona was one of the first episodes where they really ventured off of the Grimm Fairytales and into general cultural fables. While they don’t always get it on point, I’m still glad that they decided to build in more cultural references.