I know someone who swears
A childood pet cat still makes 'appearences' round the family house years after it passed through the celestial catflap.
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The magic of chutney Shakes it like an Instagram filter!,
Fri 30 Oct 2009, 19:16,
archived)
Probably the neighbours' cat coming in to steal food
Or Santa Claus.
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boris the spider,
Fri 30 Oct 2009, 19:21,
archived)