GERD can cause recurrent coughing, mimicking asthma and perhaps croup. RSV and asthma both present with wheezing and can be confused. There are, however, easily available tests that can identify RSV infections, you did not mention as to whether this test verified RSV. Sinus infections can be assumed but can only be definitively diagnosed with a CAT scan. Ear infections are easily clinically diagnosed and are usually infectious in origin. It is not unusual especially in the 'cold' season, and especially with children in day care settings to get multiple URI's which can be frequently associated with ear infections.
It is not necessarily abnormal for an 18 mo. old to have poor balance or even be able to walk up stairs.
Now that the cold season is over, if your childâs symptoms resolve to a significant degree, and if the cough resolves with treatment for his GERD, there may be less reason for your concern. If however there is no diminution of these symptoms. You should discuss further evaluation with your doctor.
LJGMD