Val, my lock-step bright to MG DD is young for grade due to birthdate (right before cutoff). She's also seemingly going into puberty later than her peers (physically slow to develop). And she's one of the few grade 6s in a 6/7 split. So most of her classmates are 12-24 months older, physically more mature for age. She has friends that have been menstruating for over a year and my best guess is that she's at least two years from menses. Oh and she's got aspergers, so she's socially delayed.
You could say she's as physically and socially out of step as a child who is double skipped. And honestly the only issues we've faced so far are aspie / literalness related. We'll try to send her to a girls school, but I'm glad now that we did not hold her back when it came up in yr2. She's in the right grade, despite the various ways she doesn't fit.
We will probably send both her and our skipped DD to a girls high school though.
