It sounds like possible seizure to me. Since she has a LOT of the criteria for possible seizure (CP, head trauma, etc) I would ask for an EEG "just to set your mind at ease"

This has happened more than once, it does NOT sound like GERD to me....sure kids with all her issues can DROOP a lot, but this is NOT normal for HER and it alarms YOU.....ask for an EEG to see if there is something NEW going on...

Hang in there

Ginny