Green’s Dictionary of Slang

a special favourite.

1919		Wodehouse Damsel in Distress (1961) 11: He’s the blue-eyed boy, and everybody else is an also-ran.
1923		Wodehouse Inimitable Jeeves 104: Till I came along he was the blue-eyed boy.
1934		Wodehouse Right Ho, Jeeves 104: She was all over me. I was the blue-eyed boy in every sense of the term.
1971		T. Lewis Plender [ebook] ’I’m not exactly a blue-eyed boy down there’.
1989		J. Morton Lowspeak 27: Blue-Eyes – a wrestler designated to be the hero in a match, from ‘blue-eyed boy’.