10mth dd had croup a few weeks back. It was horrible so big hugs to you. It broke my heart hearing her bark like that.
We ended up taking her to hospital when after the coughing fits she was gasping for air. She had a steroid of some kind to ease the coughing and it helped a lot.
After that we made sure to have the heater on, when she was cold it was much worse. We also had a cold mist humidifier next to her cot for the next few weeks until she was sleeping better.
Hope your ds is better soon.