Our 3 year old was sick one night on the Fantasy inside the stateroom. When we called to notify them of the mess, they had it all cleaned up and had us go to the medical center first thing in the morning.
He had a bit of a stomach issue through the night, but was feeling mostly better, but we still went. Doctor evaluated him, suggested she didn't think it was anything serious like Noro, but that he would be quarantined until 24 hours after the last episode. So we spent an at sea day in the stateroom and had to cancel our Disney excursion for the following morning as it left before the 24 hours would have been over.
A happy ending in multiple ways though.
1. We found out he is lactose intolerant and the stomach issues were a direct result of overdoing it on Mickey Bars and the soft serve.
2. The non-Disney excursion we did in place of the one we missed was awesome.
3. Disney covered any food ordered via room service, not just the typical menu. We got him 7Up or something similar to calm his stomach which I know we'd have otherwise paid for.
4. Disney covered any clothes we wanted to send out to be cleaned, critical as he had gone through a few sets of PJs.