My fiance's neice is living with us now, due to a foster care situation. She is 5 1/2 years old, and she goes through phases of nighttime coughing. It started before Winter and the use of the furnace. She will start to cough a few hours after she goes to bed, sometimes for a few hours, sometimes not long at all. She is not short of breath, nor is it a wheezing cough. Occasionally, she will cough so hard that she vomits, but does not "wake up" or cry afterwards. At first, I thought it might be psychological, because her younger sister does the same thing, and when they were staying with their grandmother before coming here, she would give them cough syrup and let them stay up for a while. When this niece started this coughing cycle after coming here, my fiance would go in and give her cough medicine and she would stop. Then, she would stop when you would just go check on her, without giving any medicine. That is what led me to the psychological question; perhaps she would cough louder and louder until you came in, and cough so hard as to make her vomit. Or simply the stress of a new home. After listening more closely tonight, (she coughed and vomited again), I know hers is a wet cough, not a dry one normally associated with Asthma-related issues. And she does not drink milk anytime close to bedtime. So, after that jumble of information, any thoughts?