Mine are Aristolochia tomentosa, Becky. I've had them for a pretty long time, probably 8 - 10 years, and I've gotten cats every year. They're in raised beds, which helps, since the ones I've planted directly in the ground don't do well, don't grow much. I put chicken manure around them a couple of times a year, and in spring I sprinkle lime around them and prune them to about the top of the fence they grow on, which is 6' tall.
Here is a picture of some eggs -
And here are some early instar caterpillars -
Here is a late instar caterpillar with his osmeterium stuck out -
And here is a picture I like that I took of a male on coral porterweed -
They bloom profusely every spring, but I've never gotten a single seed pod. I've opened them up, and there are lots of gnats inside the flowers, so I don't know why they're not getting pollinated.
If you don't live where pipevine swallowtails occur, you won't get them. Where are you located, in general?