From Longman Dictionary of Contemporary Englisha twinkle in your eyea twinkle in your eyeHAPPYan expression in your eyes that shows you are happy or amused a kindly, white-haired old gentleman with a twinkle in his eye → twinkle
Examples from the Corpus
a twinkle in your eye• And Beth walked between them, a smile in her heart, and a twinkle in her eyes.• She had a pleasant disposition and always had a twinkle in her eyes.• The ghost of a twinkle in her eye?• But she saw a twinkle in his eyes, and her lips twitched.• There was a twinkle in his eye as he said dryly that the procedures needed to be looked into.• Jake walked into the room with a twinkle in his eye. 