It’s normal for babies and toddlers to get stuffy noses and coughs several times a year.Most of these respiratory infections are caused by viruses that target the nose, throat and airways. The common cold, the flu and respiratory syncytial virus or RSV are some of the most common.The good news is that most respiratory infections will clear up on their own, thanks to your baby’s immune system.What is bronchiolitis?Sometimes in kids younger than 2 years, the virus moves from the nose and throat into the lungs.When the virus infects the small breathing tubes, called bronchioles, in the lungs, it is called bronchiolitis. (Bronchiolitis is not the same as bronchitis, which affects adult lungs in a different way.)Your child will have a lot of mucus in the nose and lungs and may develop a harsh cough and breathe more rapidly or even start wheezing.Symptoms may get worse while the child is sleeping. Expect your child to be cranky and tired. They will sleep more and drink and eat less.Your chil...