Gargio the Caterpillar

Yesterday, a little caterpillar appeared on the sill of our big picture window. The boys sat watching it with extreme interest as it crawled back and forth, probably looking for a way down. I was sitting on the couch talking on the phone while the boys were occupied. All of a sudden, Elijah picked up his toy guitar and started banging the window! I barked at him to stop, and came to me crying, saying the caterpillar had died!
When i went to investigate, it turned out that it had crawled halfway up the windowsill and stopped moving. I calmed Elijah down, saying it was just sleeping, and told him to watch. Sure enough, a moment later, the caterpillar turned and started coming down the sill again.
I got the idea that it might be fun for the kids to catch and observe the little caterpillar so they could learn more about them, and maybe we'd get lucky and see it change!
So i got a pickle jar, poked some holes in the top, and filled it with leaves and twigs. Then we gently got the caterpillar down from the window.

Meet Gargio (or Gargie for short). He is Elijah's new pet, and he LOVES him! 

I spent some time online looking him up, and he is a Forest Tent Moth (Caterpillar), and when he changes, he will be brown and fuzzy.
I learned a lot about caterpillars. Apparantly they are quite specific about the leaves they eat, which is why you should fill the jar with leaves from the plant you found him on. But... we found ours on the window?? But i figured since he was in our yard (unless the poor thing was HOPELESSLY lost), we had a choice between the lilac bushes, the spruce trees, and the neighbor's "whatever-it-is" tree, which hangs over our fence into our yard. I passed over the spruce, because the internet said these caterpillars like deciduous trees and shrubs, and grabbed a bit of the tree  and a bit of the lilac bush, just in case.  While he climbed all over the stick we put in, he didn't seem at all inclined to go anywhere near the lilac leaves. I took it as a hint and pulled them out, adding a leafy branch from the other tree. For a while, he just crawled around, but after a while, we noticed one of the leaves getting smaller and smaller... Yay!
I also noticed that he'd get a bit sluggish the longer he was in the house, but would move normally when we put his jar near the window. Perhaps caterpillars need the sunlight and fresh air much like plants do? Or he just likes them better than the dim and stale air of the house?
Anyway, that was our adventure yesterday morning. And of course, we drove around visiting friends yesterday, and he HAD to show "Gargie" to everyone!