Wow, Beth, that story gave me the chills. How traumatic for your daughter.
I was going to say Xanax. I used to take it for panic attacks and wished I had some before my first flight this year (first since 9/11 and I was bad even before that). I got all panicky walking down that corridor leading to the plane and thought I was gonna lose it. Looking around at all the calm veteran fliers reassures me. Having someone calm to talk to REALLY helps, too. I got so lucky on my trip to England; the cutie next to me kept my mind occupied. Then, it was really easy to sleep since I was sleep deprived from packing all night.
Oh, and no caffeine!!
Good luck! And if you hit turbulence, close your eyes and pretend you're on Space Mountain!