Little children often overhear things they are not supposed to hear, or things adults do not expect they would notice. - A proverb. * /Be especially careful not to swear in front of little children. Little pitchers have big ears./
LITTLE PITCHERS HAVE BIG EARS
Meaning of LITTLE PITCHERS HAVE BIG EARS in English
Dictionary of English idioms . Словарь английских идиом. 2012