Who said “Don’t worry your pretty little head about…”? I have heard it a few times recently and can’t find a good source for it anywhere. The best I have come across is “The Little Colonel“, a 1935 film but I can’t believe that it is the root, I have never heard of the film before. There is a similar phrase “What could have put such an idea into your pretty little head?” in “The importance of being Ernest” (Oscar Wilde). Perhaps it all came from that but someone must have first uttered one of the most condescending phrases in the language.