It's wrong to snoop through other people's things.
Sandra's daughter is getting to the age that she may be starting to have an interest in dating and romance.
Sandra wants to find out if her daughter is dating anybody.
Sandra brings up the topic of dating with her daughter and gently asks if she is seeing anyone and her daughter says she is.
Sandra reads her daughter's diary when they aren't looking and reads that her daughter has started to date someone.
Sandra's daughter understands that Sandra is curious about her life and feels okay about confiding in Sandra.
Sandra's daughter feels violated when she finds out that Sandra read her diary and loses some trust in Sandra.