(from ebookjapan):
Emiko lived happily in a big house with her kind parents, her elder brother, and her older sister. One day, however, Yumiko, who looked just like her sister, came to the house with her sister. To her surprise, Yumiko was her sister's twin sister who had been living separately for some reason. Emiko was bewildered by the sudden addition to her family, but.... A family story about what happiness is! The collection also includes "Nikkatsu Koso," "Dokodemo Yume wo," "Utaitebaso yo! and many more.