There is also Dibs the hero of a wonderful account by Virginia Axline about the treatment of a brilliant but disturbed little boy with that name. I never did stop to consider where his name came from. Perhaps she made it up out of whole cloth. Anyone with an opinion on that one?

assuming any else read the book: ca 1960, I believe

Edit: 1964, to be precise. See
http://endeavor.med.nyu.edu/lit-med/lit-med-db/webdocs/webdescrips/axline803-des-.html
for a brief description.