 Rose Giallombardo, one of the first sociologists to perform a detailed study of subculture in women's prisons, suggested that the pseudo-family develops as part of female inmates' responses to the practical and emotional difficulties of imprisonment.She explained their presence in women's prisons in the 1960s as an extension of internalized gender roles and expectations.Paralleling male and female inmate social structures, she suggests that notable differences in these cultural systems were due almost entirely to broader cultural definitions.