how do you know when to take your L.O to the doc for a cough? shes 3 months and has had this cough since she was a born (ive already told her doc) but its starting to get worse like last night she was sounded like she was going to cough up a lung. 😓 she had her 2 month apt doc said it was nothing but that was the end of June. should i make an appointment for her?