The cactus is a sign of protection. Kid are naïve and vulnerable and need protection. SANDy and her friends zip themselves into cactus suits because they think the world is a cold and scary place, and they need some armor to face it. The cactus is the conserver of water, and water means life. The cactus friends are the representation of life, or being fragile and strong at the same time… and pure like water.