In Brazil there's a custom among the mothers , in the shanty towns. When the children are crying with hunger in the evening, the mothers put a pan of water on the fire, put some stones in it and boil these stones. Then the mothers say: 'wait, wait, supper will be ready soon,' in the hope that their starving children will go to sleep, and stop crying in the meantime. That happens every day, repeated a thousand times. (CiB link)