My twin boys are only one month old, for the past week my boys have been sneezing a lot and had a little mucus I told their doctor she told me not to worry just pay attention to the sneezing. This week it got worst, their mucus has build up more and they're having difficulty breathing at times.  I remember my aunt told me I have two choices suck it out from the nose or blow through the mouth I find blowing through the mouth helps more. I use saline to help out also. They're getting  a little better I do this every two to three hours when they seem fussy.