There's something odd about Sam's favorite chair and book today...
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His kitchen mat also has those little notes on it...
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...and his food dish...
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Dad's leg, too!
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If you look closely his leash has one...
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His toys all have them...
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...and one of these tennis balls...
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This might really be a problem. Yes, I think it is. It looks like Sam might be...
...are you ready for it?
Marking his territory!