My son who is almost 3, has a low grade fever, about 101 F, with slightly rosy cheeks for about the last 8 hours. Otherwise, he is showing no symptoms and before bed seemed bright and alert - his normal self. He woke up from a nightmare a little while ago, but has gone back to sleep. He may have a little nasal congestion as he was for a time breathing through his mouth, but when he fell asleep seemed to revert to breathing through his nose. Anything to be concerned about? How long is it OK to ride out a low grade fever before using Tylenol? Should he go to Daycare in the morning if the fever remains unchanged?