We had a similar incident a few weeks ago - our two have used the litter tray with not a single problem for months, then suddenly, one did a HUGE poop in the bath. No explanation, and no repeat since (fingers crossed). I wonder if they got a bit over excited in their bathroom destruction!

You might want to think about putting a cheap lock on the outside of the door? Just one of those bar/latch things you can buy from a DIY shop should do it. Best of luck!

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Rosie, stop playing with the camera strap!