<s>[INST] My baby is 5 months old and has had a lot of mucus the last few days, so much so that he s coughing excessively and sounds very thick and has trouble breathing at night. He just started eating rice cereal last week, could that be causing the excessive mucus? [/INST] Hello. I just read through your question.It is likely he picked up a harmless viral illness. As long as he is feeding well ams seems otherwise ok, there is no need to change his diet and no need to worry. If he develops fever, irritability, or loses his appetite, I recommend consulting with your doctor. </s>