Sweet Rex

I've been working with Rex trying to get some weight on him. He's such a sweet boy. He finally put on a pound...then lost it. Very discouraging. He has good days with very little clear vomit and other days that hold more excitement, which cause vomiting more often. His trachea must be killing him. Although he was diagnosed with acid reflux I believe it's something more that isn't being found. Something that can't be explained. He is a bit lethargic these past two days and his bowel movements and eating habits have changed to something that doesn't look like a good sign. We have a vet appointment this afternoon.