Have you ever questioned as to the reasons you and your siblings are so different even though you all grew up together? Maybe even once in your life time, the thought of them being adoptive has even crossed your mind. Are you guilty yet? You might not be the only one with such speculations. According to the Psychiatrist Alfred Adler, a person who brought forwards the delivery order theory, suggested that the order where you are created in inside your immediate family, has an effect..