This year my parents found several ? of the queen page on a large fennel plant in their backyard. They took care of them by keeping them in a cage and feeding them, free of predators in their surroundings. All three of them pupated and became beautiful queen pages, which are often seen in the south, but are quite rare in The Netherlands.
The caterpillar of the queen page has a beautiful pattern, which was an inspiration for the one I drew in the middle.