I am so very sorry that your precious little Korey will be spending Christmas in the Hospital. It really hurts to have one sick with diahrrhea and so scary too. My little 3.5 lb. Peppy had a bout earlier this year which started as loose stool and went to bright red blood dripping from his rectum within a matter of two hours. Fortunately for me our regular vet practice as a doctor on call 24/7 so he would up at our regular practice and spent 4 days receiving intermittent iv fluids. The day I was to bring him home he started vomiting so he spent another day. It was terribly lonely......
I will keep Korey in my prayers as well as you. Sending hugs your way