The Mama Monarch of these three early instar caterpillars deposited her eggs on the buds of Common Milkweed. I see this behavior often, not as much as on the leaves, but often enough.
The three hatched and stayed foraging on the flowers, where they were well camouflaged in their early instar paler colors. By the third molt, they had all three moved off the blossoms and were foraging on foliage.
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