My baby is 3 mo 2 weeks old (5 weeks premature) and has sounded hoarse since yesterday. This has happened once in the past but they thought it was due to reflux. His reflux is much better and has not required medication. He has been chewing on his hands quite a bit for a few days as well. Yesterday was gassy and fussy but doing much better today. No other symptoms presenting. What could cause the hoarseness?