The engine room is loud and hot and dirty, but Kaylee is sunshine smiles and laughter. She brightens a room, makes things look better than they are. This is of course because Kaylee is such an optimistic, frank girl herself. She says what she feels, feels what she says. There isn't a dishonest bone in her body. She chases River around the ship and plays with her when Simon is too caught up in his work to remember how to play, and relax. There's dirt smudged on her nose and under her nails, but she genuinely loves Serenity and all of the people on it. Kaylee is like the spring, all bright colors and sunshine and warmth. She fills River up with her happiness, pours into her the sunshine of her smile and paints her in the colors of springtime mornings.