Thanks again SAS! That was a very good article on the problem!

Fister has made a tiny puddle outside his box and is now sleeping in the chair. He has been under the bed a few times today, which is not normal, he usually sleep ON it! He is not complaining loudly yet, but I'm sure he will later. John spoke to the vet while I was out and wanted me to ring back, but I haven't been able to get hold of him yet! He wants to know what food he's had lately and said that it was best to change betweeen the dissolving diet food and the preventive. He's only had the dissolving. It looks like we'll have to wait till tomorrow, hopefully he has time then!!

Will keep you updated!