One of my boys *about 5 months* is sick and I dont know what's happening to him! His sister died in the same way not long ago!! We woke up and he was just lethargic and drooling, he also looked like he was trying to regurgitate. We waited it out and then took him to a vet. They couldn't find out what the problem was and gave him some pain meds and anti nausea meds. He is now worse and his jaw around his teeth has started to swell. He isn't choking as the swollen jaw and it's been 2 days, the vet said he dosnt have a tumor she could feel, it's not his teeth as he was trying to regurgitate long before the swelling. His sister died over night once the swelling started and we have no vets in our area that will help us with our rat. Any ideas???