Thirteen-year-old Opal starts a blog to satisfy her mother, who thinks she might lose weight by recording all she eats, but instead Opal starts giving advice and discovers that she is much better at giving it than taking it.

Missing her mother who died last year, fourteen-year-old Sofia finds an anonymous outlet for her personal questions and deep, dark secrets in the Dear Kate advice columnist until, much to her horror, Sofia's father starts dating Kate.