As children progress from infancy to the early years of childhood, they begin to understand their relationship with the world around them, especially to the objects they come into contact with. They begin to comprehend simple cause-and-effect relationships, learning that their actions often cause a reaction. This development, combined with the newly acquired motor skills of grasping and shaking, makes multisensory toys highly appealing to toddlers. Toy instruments, for instance, reward this understanding, because a child's motion-pounding, tapping, clapping, or shaking-produces a noise. The same outcome occurs every time the child repeats the movement, reinforcing the relationship between her motion and the noise. So while not all children become musical prodigies, many toddlers delight in and learn from the sounds they make with toy instruments.