Choose the remedy that seems the closest description to you or your child's cough, temperament and symptoms. If the the child has just begun to show signs of Croup, start with Aconite until symptoms change then use Spongia. Once taking Spongia, wait until symptoms change and follow up with Hepar sulph.
These remedies are about $7 a piece at the health food store~ probably cheaper than a co-pay to the doctors office. Likely a trip to the doctors office will end in a prescription for Dexamethasone; this drug has side effects such as sleep disturbances, indigestion, mood changes and nervousness (that's all a young child needs!)
Excellent herbals for Croup are Elderberry, Lobelia, and Mullein tincture. All can be given to young children under 2 years of age but Mom & Dad must quarter the dose for baby. Between 5 and 10 drops of any of those tinctures is adequate every 4 hours. These are all available at vitacost.com or at a health food store and are about $10-$12 each.
Eucalyptus Oil in a diffuser (at night in the room) and applied topically (diluted) to the chest is also a great starting point.
Other suggestions are making sure the the room of the "Croupie" has nicely humidified air. If I think of anything else I'll be suer to post it. I welcome your thoughts and experiences on the natural treatment of Croup! Thanks!