Suggest Treatment For Tracheomalacia In A Child

My daughter who is 3 sometimes has a flutter in her breathing when she gets all worked up, like after running around. Initially the MDs had thougt it was a case of tracheomalacia and would improve as grew. So, when the condition persisted at age 1, a barium swallow was done but results were inconclusive. The flutter sound, although infrequent, still continues and is the same - has not changed, worsened or improved. It doesn t happen all the time during regular breathing so replicating the condition in an office setting is difficult. What could the issue possibly be?