Sitting in here listening to the coughing coming from Emily's room...
Emily has a mild, baseline chronic cough that is sometimes random, but does come more often on exertion (the asthma component of her cf acting up) and in the morning shortly after waking (whatever junk settled in her lungs overnight.) And of course she coughs a lot during tx. Allergies are not an issue for her; she's been tested. When she's sick- mild bugs or sinus infections result in lots and lots of coughing shortly after laying down at night due to postnasal drip but then things will generally subside; if it's her lungs that will bring on coughing that continues night & day, no matter what, and gives an especially severe quality to the morning cough.