There should be free movement. There's something about the monarch butterflies having freedom of flight and freedom of mobility that many humans don't have. We found out that in Mexican folklore the monarch butterflies arrive in Mexico at the very beginning of November–right around the Day of the Dead. The day after the Day of the Dead is the Day of the Children, and the mythology is that the monarch butterflies are the spirits of dead children returning home to Mexico. There are international protections for monarch butterflies, while there are children dying in the desert–children whose names are unknown–just a belt found with a name on it. That idea of not being seen, not being noticed made it seem like the migration of monarch butterflies was a great way to put these children's stories out and into people's consciousness.