Trying to help her hard-working father and twin sister to adjust to life in Stoneybrook, Abby Stevenson becomes the newest member of the Baby-sitters Club and shares her first adventure.

Abby Stevenson and her twin sister, Anna, the new girls in town, are trying to adjust to everything new and help their hardworking, fatherless family.

Trying to cheer up her twin, Anna, who has been diagnosed with scoliosis, Abby fears that the condition is driving them apart when Anna seems to not want Abby's help and begins to do things on her own.

When her troubles in school culminate in her being dropped back to the seventh grade, Claudia struggles with feelings of failure while adjusting to classmates outside of the Baby-sitters Club.

Writing a Thanksgiving play for the third-grade class she coaches, Claudia is disappointed when some parents object to her less-than-traditional themes, and she must choose between letting the other kids down or fighting censorship.

Valentine's Day is Abby's least favorite holiday. Mushy stuff like valentines, red hearts, and a school dance turn her into a Valentine's Scrooge. When Ross Brown, a perfectly nice guy in Abby's English class, invites her to the dance, Abby tries to set him up with her twin sister, Anna.