A picture book on twinship, for ""singletons"" wondering what it would be like to have a double, and for all those puzzling out what it means to share, for fraternal twins, a birth date, and for identical twins, so many other features. Miller's large full-color photographs work best to display the ways twins do and don't look alike, and to show their roles in the family. Scott discusses the concerns other siblings have with twins in the family, and the importance of treating children who are twins as individuals. A lengthy afterword instructs adults in how to use the book, and, for parents of twins, in how to field intrusive questions. No explanation of where twins come from appears in the body of the book, although Scott includes several explanations for adults to try out, and refers them to another children's book on the subject. A fussy layout and a typographical treatment that arbitrarily emphasizes words in the text do not detract from the smiling faces of the brothers and sisters in these pages.