A Closer Look Revealed Something Else
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If it was a dog then the couple would at least have an idea of what they were in for. It’s possible that Anna’s assumption relaxed her a little, or at least enough for the animal to unfreeze.
It stood up and that’s when Anna realized that it wasn’t a dog. The tail was large and very bushy given the size of the rest of the animal’s body. That’s when it dawned on Anna what this was.