What they did with Greta in the Young Justice cartoon (the episode was called 'Secrets', if you don't know, and was probably meant to air closer to Hallowe'en than it did) was both interesting and sad. The way it ended could mean we'll see her again, or it could mean we won't.

�They planned their campaigns just as you might make a splendid piece of harness. It looks very well; and answers very well; until it gets broken; and then you are done for. Now I made my campaigns of ropes. If anything went wrong, I tied a knot; and went on.�
-- Arthur Wellesley, First Duke of Wellington