"It is a parent's worst nightmare that your child could go out for an evening's entertainment and this sort of thing could happen, " she said.

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When you are facing every parent's worst nightmare in losing a child, surely it must be a difficult decision?

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We can ask if there is adequate education for the parents of children with mental challenges to help them deal with the nightmare of knowing that their child could be at risk for this type of behavior.

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For poorer parents, juggling the twin demands of work and child-rearing can be a nightmare.

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Even during peak holiday travel periods, adults, of course, outnumber children on planes, and airlines have to balance the needs of parents with other passengers whose nightmare is a long, crowded flight next to a noisy child.

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She cited Samuel Taylor Coleridge's "Rime of the Ancient Mariner, " with its frozen polar wastes and specters of "Nightmare Life-in-Death, " which as an 8-year-old child she had heard the poet recite in her father's parlor, and she made several dark allusions to the alchemical experiments of Paracelsus and Cornelius Agrippa, two Medieval figures with whom Percy had become obsessed during his studies at Oxford.

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