Consider the boy who is taking care of his baby sister while his parents are in town shopping. He decides to go fishing and he takes her along.
"I'll never do that again," he tells his mother that evening. "I didn't catch a thing."
"Oh, next time I'm sure she'll be quiet and not scare the fish away," his mother says.
"It wasn't that," the boy says. "She ate all the bait."
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