You may bring up blood when you cough, or you may notice spots or streaks of blood in your phlegm. Both instances need medical attention. Bacterial infections can also cause bronchitis.

If your baby has an allergy, they may also have vomiting, irritability, and blood in their stool. BabyCenter Community member PaulaBM19911 says "My babe had lots of mucus in her poop, so the ...