Have you ever used spongia testa as a natural way to get rid of the croup instead of a steroid?

No: Truly homeopathic "medications" are made by repeated dilutions, so that the ingredient is not really in the medication anymore (just the "essence" of it remains). That means there is no active ingredient left to cause any benefit. However, that also implies that the homeopathic "medicine" should be pretty harmless, unless some other non-homeopathic ingredients were added.

Yes: ...And it worked pretty well. However, if the croup is really bad and the child is having trouble breathing, i still opt for the steroid. In those situations i may use the spongia tosta to alleviate the symptoms until the steroid kicks in and decreases inflammation in the throat.