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My JR is about 8-9 yrs old (he was a rescue, I got him about 3 yrs ago) He has gone from a perfectly healthy dog overnight to not being able to walk. He moped around a day or so first (has had this behaviour twice in the past year - took him to the vet and they found no cause, and it cleared up as quickly as it came) but this time it affected his legs and he cannot get up. The vet thought he might have white shaking dog syndrome as he was also shaking a lot. He has just finished his 3rd day on Prenisone (20mg) but not much improvement. Now he is also having severe cramping and diarrhea. Has anyone had a similar situation? - I am desperate to save this brave little dog.