I learned this hiccup cure, which always works for me, from my Russian grandmother: Have the child stand up straight, shoulders back, with her hands locked behind her back. Then have her swallow a few large sips of water while another person holds the cup. The hiccups should resolve in about ten seconds. I'm not sure why this works. It may have something to do with stimulating the phrenic nerve when one swallows while standing straight with the hands behind the back.
