Seablue, I bet if you ask for reading material in the Girls forum at OASIS you'll get some answers. There are some parents over there with AS girls.
Anecdotally (we have a female cousin with AS), I'd say they get missed because:
--many are "sociable"-- ie they want to relate and have friends even though they have poor skills for doing so. (This is also true of some AS boys.)
--they don't all have huge meltdowns; sometimes they are just as anxious but many internalize it, so they look extremely "well behaved" and schools can ignore them.
--they are often taken advantage of because they can't read social situations or the intentions of other kids; again this is often mistaken for compliance.
--they often display play behavior (ie, they are not lining up toys, but playing with them)-- but their play can be heavily scripted, repetitive, or echolalic. It looks more like real play than the play of AS boys does, but it's still not functional.
I would watch for real, back and forth conversation: can she build on someone else's idea? Or does she just lecture?
Starting to see AS in family members is pretty usual once you suspect it in your child. Our family is sprinkled with AS-type quirks... and some adults who are clearly diagnosable but were missed because the diagnosis didn't exist back then. For me it just confirms the genetic nature of ASDs.
DeeDee
