Conversation so far:
what is the history of the Academy Juvenile award?
the Academy saw the need to establish an Honorary Special Award specifically created to recognize juveniles under the age of eighteen for their work in film.
what happened when the Academy Juvenile award was first presented?
there were several juvenile actors who were instead nominated in the competitive Best Supporting Actor/Actress categories.  All of the nominees, however, lost to their adult counterparts in their respective categories.

Question: what changed?
Self-contained rewrite: what changed in the Academy Juvenile award were several juvenile actors who were instead nominated in the competitive Best Supporting Actor/Actress categories and with all the nominees, however, losing to their adult counterparts in their respective categories?