What Causes Watery Eyes In Children Suffering From Fever?

My six year old son has had a fever the past two nights. Last night it was 103, but has been in the 100-101.5 range all day today. About an hour ago, his eyes started watering and his right eye is puffy. He s been watching TV and I m worried that he has light sensitivity and that s whats causing the watery eyes? He s been eating today, but not as much as usual, and we re trying to keep him hydrated. I ve looked up some things online and some websites say to seek a Dr s attention if red, watery eyes is accompanied by a fever, but I can t find any more information beyond that. Any advice?