Intants lack concepts of furniture, reading material, and sports equipment. They also lack more specific concepts such as baseball mitts and books. Thus, Shawna does not understand the scene in the same way as her older brother. However, without knowledge of child development research, an observer would not know whether a baby as young as Shawna has formed other concepts relevant to understanding the scene. Has she formed concepts of living and nonliving things that help her understand why the dog runs around but the books never do$?$ Has she formed concepts of heavier and lighter that allow her to understand why she could pick up a sock but not a dresser? Has she formed concepts of before and after that allow her to understand that her brother always puts on his socks before his shoes rather than in the opposite order? Or is it all a jumble to