Fabulous!
I thought this might be about artificial food... I had 3 black swallowtail cats that pupated, and i thought they would probably overwinter as chrysalises. However, 1 eclosed 2 days ago... and although we're still having unseasonably warm weather, there's just no way there's enough time for eggs, cats, and overwintering chrysalises, even if s/he could find a mate (will have to look up how to tell sex).
So we're not releasing this one but keeping it as a "pet," putting in the last of the season's garlic chive blooms (a favorite) and "keeping her comfortable." I just made her some nectar (in a little container with a sponge). I feel guilty ("butterflies should be free!" is jangling in my head) until I see how much fun Joyanna and her friends are having with an up-close look at such a little beauty.