Because, yeah, it is helpful to know what's supposed to be happening when in a general sense so you can have realistic expectations (I remember thinking that a one - year - old could probably speak in complete
sentences back before I had one of my own), but at the same time kids are so varied and variable that you can really make yourself worry
over things that don't mean
anything.
I will look for issues like overused words, too many adverbs, purple prose,
sentence fragments, confusing
sentences,
over or under describing, cliche phrases, awkward or unnatural dialogue, and
anything else that prevents your prose from shining.