I an older post below I talked about several cats I found right after a hard freeze had killed down all my tropical milkweed here in central MD. I brought them in and they all pupated, even a couple that were HALF the normal size.
Suprisingly, all seven of them eclosed as adult butterflies, and the two little ones were the tiniest monarchs I've ever seen -- about 2 to 2.5 inches across. I kept them all in a butterfly castle and fed them gatorade by spraying it on artifical flowers. Most gradually died over the next several weeks but I had three that lived well into January, and one that lived until February 18th! It was neat having butterflies in the house when there was 30 inches of snow on the ground.
Just this weekend I got 100-plus tropical milkweeds started under the lights, and will get some zinnias started in a few more weeks.
I'll try to attach some pics if I can figure it out.