What to look for to see if my 4 year old has symptoms of cystic fibrosis?

Stinky poo. If your kid has poop that will clear a room from the stinky smell, and the sweat tastes like salt i might consider that diagnosis. Most will be well into those symptoms by 4. If your kid only has recurrent respiratory issues its more likely from other origins like allergies or asthma. Share your concerns with your doctor.