Love the link Snadger, and the Benny Hill music made me chuckle. I learnt early that the way to give this cat a tablet is to hide it in a teenie bit of tinned food, then carry on filling the bowl and letting the other cat join in with the unmedicated food (yes, this same self cat also has hormone problems that means he has very bad skin unless he has hormone replacement tablets

)
I never really thought about the new baby as he was find when my first was born, but the I suppose each situation will be different for him and maybe he just reacted to this one...? He seems perfectly normal every other way - still as friendly as normal, etc
Okay... I'm getting out the white vinegar very soon and rescuing the litter trays from the loft - I've just to figure where to hide it as we have a very open planned house and no utility room etc. Where does everyone else hid theirs cat's litter trays? I just figured that I shouldn't have to put any out as they had outdoor access all day.. Oooops.
Thanks for the link SeaSprout, having a good nose now.
We've tried the radiator thing before and they didn't use it.. maybe we'll have another go? I might try out a nice deep dark box with an old towel on the landing too (or my favourite magazine, lol)... you know what cat's are like!
Thanks everyone. I was starting to dispair a bit, and started to have thoughts of not keeping him much longer, but then couldn't face my conscience if I'd done that as they're too much a part of my family, and we got them as rescue cats and would have felt awful putting them through that again...
OH is taking this cat to the vets on Saturday about his skin, and I've already asked him to mention about his 'mental health'.
Thanks all for the support and suggestions. I'll certainly post back with updates