Sounds like a case of what I call airport anxiety. With three kids (i have two young ones) I can imagine it might not be easy. We flew down last year on my son's first b-day. He screamed an carried on for 4.5 hrs from Chgo. NOT FUN for anyone on the plane especially when we landed and the gate was occupied for 30 minutes while he screamed some more.

With that said, I'm not sure what we will do this year to make it easier to sleep as we are all (except the 21 month old) counting the days until our return to Aruba and will be very excited on the eve of the return. Last year, we had a pretty good party/bbq at the house the night before our departure. A few cocktails made it seem easier to fall asleep. Try that, but drink some water before bedtime so there is no side affect from the alcohol

If need be, get a sample of ambien or lunesta and you will sleep for 5 -6 hrs

i wish I could give more/better advice. Once you get to Aruba, my next anxiety occurs when I realize I have to leave. That's why I booked two weeks this year for the first time