Quoting Barnett Babies:" Hopefully he will eat some Yogurt any kind with the Active live cultures in it- It puts back the good bacteria that are lost during vomiting and diarrhea !"
Quoting Squeaky McGee:" Dairy might upset his stomach, though. Typically, the BRAT diet is recommended, since it's bland (bananas, ... [snip!] ... it's bland (bananas, applesauce, rice, toast). Also, I'd suggest Pedialyte, to replace the electrolytes lost with the diarrhea."