"Picking off the kiddies"

I have seen some debate over this on other sites. Some people have mentioned that Zodiac's use of the word "kiddies" in one of his letters is a big deal because most people didn't use that word back then. I wasn't alive, so I have no idea, but I did find a newspaper article with the title of "3 Indiana Kiddies Slain." If a newspaper is using the word in the title of a story then I doubt it was that uncommon of a word.

what year was this printed?

The Virus wrote:what year was this printed?

I'm not sure. My dumb ass forgot to put that. I could look again, but I'm lazy. I want to say around 1965-ish.