It's a teachable moment only if the subject is open to teaching, and depending on the severity of the autism that isn't always the case. It sounds to me like the mother knew that a melt-down was a possibility and instead of re-scheduling to another flight so that she could ensure her child did have a hot meal before hand, she rolled the dice and hoped the kid would make it through the flight they were already booked on. And when her plan went to crap then she expected the airline to save the day.
she expected the airline to save the day.
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I am not sure microwaving a meal is too much to ask.