My Labrador put me through a scare a couple of years ago where he was drinking excessive amounts of water and having accidents, including in bed. Thought it was renal failure. It wasn't. Still don't know what was going on, but he's fine now. Anyway, used it as a perfect excuse to get a plastic mattress cover; this one:
LeakMaster - Fitted Waterproof Mattress Cover. It was ... Okay. Crinkled awesomely, and protected the mattress - for a little while. Very quickly, though, it got brittle and hard, and every time I flopped down it'd develop another crack or split. In less than a year it was in pieces and provided no protection.
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