What Causes Recurring Cough With Phlegm And Food?

My child, who is 2 years old now, has always from the time she was born had some sort of small cough. Her pediatrician has never been concerned about it and always related it to colds she got from daycare or teething. Just recently, she has begun coughing more, to the point where she throws up phlegm and then whatever she ate previously. She has experienced this at least once per day for the last week or so. Not sure if this is relevant, but she did contract pneumonia one day after birth and was treated in the NICU for 3 weeks before recovering fully. She also had a barium swallow test during her time in NICU and it was confirmed that she also had reflux. She was never treated for it as she never spit up her milk. Could what she is going through now be reflux? Asthma or is there someting else to be concerned about??