Last night we had a rain storm blow through and I didnt think anything about it, as our horses have a shelter to go into (which they DO use) and it wasnt too cold. Maybe 40* at the most. Well when I went out to feed this morning I wanted to feed them in their shelter so if any more rain came, they wouldnt get all wet and cold. When I looked at my horse his shoulder, butt, and legs were all shaking, shaking terribly! I've never seen him shake so bad! Is he sick? Or is he cold? Should I get a medium light water resistant turn out blanket? I told my parents and they said "oh, hes fine, hes just a horse..." But I dont think so, if he wasnt cold I dont know why he would be shaking... something seems wrong. Or maybe, Im just over worrying and hes fine? Why do you think he would be shaking so bad? His legs looked like a leaf in the wind... it was pitiful! I have a blanket for like 30 below, but not one for 50 and below... maybe I should invest in one? He is quite chubby, not at all on the skinny side. We rescued him about 9 months ago... And the other horse, wasnt shaking at all, which make me wonder whats wrong...