Just what it sounds like. Journalist Saline (Dr. Snow, 1988) and Pulitzer Prize -- winning photojournalist Wohlmuth present brief portraits of 36 sets of sisters. Wohlmuth's intelligent photographs capture a range of sisterly feeling from the severe to the giggly, while the texts function as plainspoken testimonials to the pleasures, difficulties, and duration of the sisterly bond. The sisters come in groups of two and up; some are infants, some in their 90s; two sisters are Sisters in the Roman Catholic Church; and, family values embracing transsexuality, one sister used to be her sister's brother. Some sisters are anonymous and others famous: Coretta Scott (King) and Edythe; supermodel Christy Turlington and her two sisters, Erin and Kelly; the Mandrell sisters; Wendy Wasserstein and her sibs, Sandra and Georgette. But the point isn't celebrity. The point is to celebrate the enduring relationship between girl-children.