Sounds like croup...

Fever that comes and goes? Check.
Congestion and difficulty breathing? Check.
Occasional vomiting of phlegm? Check.
Hacking, barking cough? Check.

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Run the humidifier in her room? Check.
Watch closely to make sure she can breathe? Check.
Hug her as often as she would let me? Check.
Stay calm and pray that she recovers soon? Check.