wow. this sounds rough.

it sounds like she needs to be in regular continuous therapy and back on some sort of calming medication. from what you've said, it doesn't sound like ADHD is her problem. i could be wrong though. it sounds like she desperately needs/wants attention...and that could come from getting a lack of it from her birth parents. it could also be that she saw your parents' trip as abandonment and it scared her. it could be many things. she needs to see a competent psychologist who can correctly diagnose her and talk with her to find out the problem. my best wishes for you and your family and parents... i hope this poor little girl gets the help she needs soon.

((((((((((concernedsister)))))))))))))

PM me anytime if you need/want to talk.

-shadow