It surprised us that we still didn't have any caterpillars on our milkweed. When we started checking we noticed that eggs had been opened but not eaten. That is not normal, because the caterpillars eat their eggs. So when I found an egg, we brought it in. The next day we found 2 more eggs. A few days after they hatched I started to worry. One was definitely a monarch caterpillar. However the other 2 looked odd. Google told me they weren't deformed or sick. It was simply another specie - Queen butterfly caterpillars!