I have just been on the internet researcing food additives and OMG, DD eats grapes and strawberries every single day and sometimes has a big serve of these right before bed. It says to avoid these fruits. This certainly could be the problem, I cant believe some that I thought were healthy and good for her are actually making her unwell.
Hmm off to do some more research.

Lulu: i did stumble across an old post of yours too in regards to your DD I think it was having a reaction to grapes which you related to sleeping problems.