Little angels will have a ghoulish good time in this getup.
Horns: Make the basic horns. Paint them red.
Tail: Straighten a wire hanger, cut a 23-inch section, and bend over both ends so they won't poke. Duct-tape the wire to the long edge of a 9- by 21-inch piece of red felt. Roll the felt around the wire and seal the rolled edge with tacky glue. Cut two identical triangles out of cardboard. Tape one to the end of the tail, then place the second on top. Completely cover the cardboard sandwich with masking tape, then paint it red. To attach the tail, hook the plain end onto the child's waistband.
Top off the all-red costume with a pitchfork made of two cardboard "W" shapes sandwiching the dowel, taped securely and painted.