For Halloween I would like to get my chi a superman costume so I could take it with me trick-or-treating. is this a good idea/ does this make the pup upset or anything?? And does anyone know what size it might take for being a short-haired four month old chihuahua?? There are Zeroes, 1, 2, 3, 4, 4.5, and 5. OFcourse with it having healthy diet and exercise!