Latest: Took Ratty into the vets this morning first thing. Vet has just told me he found a bladder stone on the scan, about 3mm across he reckoned. He's going to operate to remove it, and get it analysed. He may have to keep her in overnight the poor thing - but I know it's for the best in the long run. No idea what it is yet, or how long it's been there. So glad we got her to the vet when we did. Bless the poor little sausage!!