I'm so sorry about your dogs. The same thing happend about 2 yrs ago to our Sasha. We rushed her to the vet who said she had been poisoned. As she was getting worse with treatment we took her to Texas A&M vet school to learn that the symptons were similar to being poisoned but it was a blood clotting defect. The vets said that they had been seeing alot of it but could not give us any explanation as to why. We too lost our girl. Several weeks ago we found another puppy - 1/2 rot 1/2 dob at a rescue league and would you believe her name was already Sasha. Like the other she is the joy of my life and keeps me laughing - especially when she takes her rubber toys into her little wading pool. Sure beat the heck out of her dropping them in the commode.