After exposure to rsv, my 4yr/o developed rsv/cold. sick about 6d, mostly cough/runny nose. no breathing probs. see dr or continue treating symptoms?

Keep observing: If no fever or severe cough or breathing problems, then recommend treating the RSV as the typical cold virus it is for children this age. If kids are healthy then RSV is only generally dangerous for young infants and toddlers. Recommend saline spray for the nose and a vapor rub for the chest to help the symptoms. See your doctor for fever, worsening cough, or any new concerns. Good luck!