Prednisone is a drug that has to be tapered off. My oldest son and I have to take it regularly for our asthma too. He can get moody also, when tapering off, and I have had horrible body cramps when ending prednisone. The DR says thats the "risk" (benefit out weighs the risk)we have to deal with to breath, but I wish there was a better way. Sometimes the Dr will give another packet to help out with it, and it helps. Have you talked to your prescribing Dr, after the ER? Sometimes, the ER is not as good about treatments for young children.