So sorry mary r....the worst is when we don't know why. My NR of five years (Owena Owie-Head, in All Squirrels Go to Heaven), died after just a three-day lack of appetite. She was perfect for five years before that, except that she had suffered from seizures her whole life. BUT a seizure didn't kill her -- her liver failed! She ate a perfect diet, was never sick a day in her life. The vet who necropsied her body told me she was perfect.....except for her liver. What the heck? It will haunt me forever. So I get it.