Cats can appear happy and healthy because they don't like to show weakness of any kind. It's their natural instinct because they don't want to attract predators. Puddy (all my cats, really) waits until she's really sick before she cries, as is evident by her latest URI w/bloody urine and blood clots. Had she shown any symptoms of illness whatsoever, off to the vet she would've gone. So tell your vet to get w/the program. Time's a wastin'!