a wolf-like child will have an evil heart—aggressive designs; wild (/sinister)ambition; vicious scheme; wolf-hearted; wolfish nature
? ～，非是，莫喪羊舌氏矣。(《左傳·昭二十八年》)A wolfish child will have a wild heart. None but he will destroy the clan of Yangshe.
? 諺曰： “～?！?(《左傳·宣四年》) There’s the common saying，“A wolf like child will have an evil heart.”/操曰： “吾素知呂布～，誠難久養(yǎng)。” (《三國演義》151)“I know Lu Bu quite well，” said Cao. “He is a wolf with a savage heart.and it will be hard to feed him for long…”/我們就在談判桌上跟它斗，向全世界人民揭露它的～； …… (楊佩瑾《劍》71) …We must struggle against them on the negotiating table—exposing their aggressive designs before the world’s people.
? ～難料，看跋扈漸肆咆哮，挾勢辜恩更堪惱？ (洪昇《長生殿》) Who can judge the ambition of the wolf cub丨That starts to snarl and glories in its power，丨Forgetting the gratitude it owes?/可笑玄宗不覺其～，卻要信他是真心，好不癡心。(魯迅《中國小說史略》111) The emperor failed to perceive the reprobate’s ambition and believed him to be sincere; the very height of folly!
狼子野心
wolf cub with a savage heart;wolfish nature with wild ambitions; aggressive designs of the wolves; vicious and ambitious design
狼子野心lánɡ zǐ yě xīn
狼子：狼崽子。狼崽子雖小，但有兇惡的本性。比喻兇惡、殘暴的人本性難改，有狂妄的欲望和狠毒的用心。wild ambitions, the aggressive designs of the wolves