This chapter begins with a quotation from a letter that Emanuel had sent Melanie Klein after he had heard of her engagement. The letter becomes clear from P. Grosskurth’s biography of Melanie that the relationship between brother and sister was extremely strong and important to them both. The opening quotation comes from a letter that Klein’s older brother, Emmanuel, sent her in 1901 following her engagement to Arthur Klein. Emmanuel was twenty-four at the time and Melanie was nineteen. In her writing, Klein is quite certain of the efficacy of sibling love on the developing psyche and she puts much greater emphasis upon its importance than does Freud. Klein makes an interesting distinction between sibling incestuous attachment and oedipal conflict. She writes that: “The existence of sexual relations between children in life, especially between brothers and sisters, is a very common occurrence”.