What Cases Swollen Neck Lymph Nodes, Rash On Stomach And Fever?

lymph node in neck a bit behind the ear is noticeable, and daughter has a slight pink rash on belly and back, seems to have had a virus, and had slight fever, but fever gone today, is there anything to be concerned about please, should she see her doctor or should I see if she recovers as she seems much better in herself now, thanks, the glad moves when pressed a bit