兄肥弟瘦的英文是「surrendering oneself to the cannibal bandits to substitute for his younger brother they captured , s」
xiong fei di shou
旧喻兄弟相爱,临难争死。
《后汉书·赵孝传》:“及天下乱,人相食。孝弟礼为饿贼所得,孝闻之,即自缚诣贼,曰:‘礼久饿羸瘦,不如孝肥饱。’贼大惊,并放之。”