The Impact of Opposite-Sex Younger Siblings: A Hypothesis Concerning Gender Differences

The first year of two psychoanalyses (a prelatency boy and a prelatency girl, both with opposite-sex younger siblings) is examined and compared using an approach to the psychoanalytic data similar to grounded theory. For the girl, her envy of her brother's penis seemed to be a response to her sense of abandonment by the mother. For the boy, the birth of his sister seemed to have triggered concern about the integrity of his body, although separation concerns were also present. The findings in these two cases are consistent with Phyllis Tyson's (1989, 1994) conjecture about the difference between boys and girls. Because of boys' body difference from mother, the threat to their body integrity (expressed as castration anxiety) is more common than in girls and begins with separation–individuation. In contrast, girls do not usually experience such concerns with their body integrity because their bodies are like mother. Intense penis envy that may be observed in girls is more reflective of the loss of the mother than an issue of concern about their body integrity. The implications of the contrast between the two cases are discussed.