Hi my 21 month old toddler has had diarrhea the past 3 - 4 days. He has been refusing to ingest anything besides milk and rice cereal. If I try to get him to eat anything else he gags and on one instance puked. His poops have been gray/white/tan in colour as well. He has been generally happy and playful though. Does this just sound like a stomach bug or could it be something more serious?