When I went outside to put the hounds to bed last night, Mavis was lying in one of the natural areas. She wouldn't get up. Hubs and I took her to the emergency vet. She had a tumor in her abdomen that had ruptured and was bleeding. The vet said she believed Mavis probably had a lot of tumors. It is likely those times she was acting 'off' a tumor was bleeding but then stopped. We had to put her to sleep.