I have two twelve year old Tonkinese cats-I have had them since they were kittens and they have been fed on Hills dry food until a few months ago when I switched to Royal Canin senior because the female kept being sick.I had her checked by the vet who said she was healthy.However she is still sick every morning :(Its usually before I get up and the cats are locked in over night.Unlike her brother she doesnt go beyond the garden-and only rarely goes that far!She was very ill with a blood parasite thing a couple of years ago and has a bit of arthritis in her front leg.I just wondered if anyone has any feeding suggestions to help her.There is always fresh water available.thanks.