My little boy was sick last night, he's a few days older than Roman and has never vomited like it, a huge volume came out. He had no fever, no rash, no other symptoms and was totally back to his normal self in seconds. He's not been sick since, and has taken on plenty of fluid, but you can bet your life I stayed up half the night staring at him, checking his breathing, his temp, just making sure he was alright. Not clearing off to the other room and asking strangers for their diagnosis...