we always have a carry on bag stuffed with snacks for the trip....
we travel for about 30 hours, so even with two meals on board the long haul flight, the kids need food/snacks along the way..
typically, we have pretzels (several bags, since the adults like them too), cheerios (the plain, nonsugar kind), crackers, rolls/bagels/bread....
also empty water bottles -the size the kids like to drink from...that have the nice drinking top..
then i fill those on the plane with water from the flight attendant...so the kids have water to drink during the flight...
i also bring a box of plastic ziplock bags....so i put the pretzels or whatever into them for the kids to eat....little serving sizes...
everything i've named above can be brought into the US without any problems...
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