My 9-year-old grandson has run a low-grade fever, usually in the evenings for 7 days. He also has a harsh cough. He has been very healthy up to this point. His lungs have been x-rayed = no signs of congestion, but swelling in one upper lobe of one lung. His mother is extremely worried, as two doctors have mentioned cystic fibrosis. One doctor says there is almost no chance of his having this as he has no other symptoms.