Almost 1 year old STILL had a cough!!! Help!

Justina

My baby will be 1 in about 6 days but he has had a cough since the week of the 18th. I was sick too so he went to the Dr with me and we both got checked out. We left with the Dr saying we both have just common cold. The day after Christmas is when his cough got worse. It started to sound more like a barking dry cough. I watched him for two days and there was no sign of fever. On Friday night I took him to the Dr and she said there is no need to worry just keep doing saline for nose and using humidifier. She also gave me a childrens allergy Zyrtec. I guess my question is has anyone's baby had a cough this long and when will it go away? Im guessing with his cough it sounds worse than it is but I just hate seeing him so miserable for this long but both times Dr said he is fine just keeping doing what I'm doing. Just looking for some extra advice.