When Kristy gets a regular sitting job at the Kilbourne house, she has to wonder: Doesn't Shannon Kilbourne, associate member of the BSC, have time to take care of her own sisters? The answer, unfortunately, is "no." Shannon is too busy to deal with her sisters. But they will not be ignored.
First, Tiffany and Maria try to help Shannon — by "cleaning" her room and "correcting" her algebra homework. When this doesn't work, Tiffany and Maria decide to make Shannon's life harder. Can Kristy manage to forge a truce — or will the Sister War rage out of control?
Kristy finds herself in the middle of trouble between her friend and fellow baby-sitter, Shannon, and Shannon's two younger sisters, Tiffany and Maria. Kristy wants to help the sisters smooth out their problems so that everyone will be happy.
The idea for Kristy and the Sister War came first as a title — we liked the title so much that we decided to write a story to match! Kids often ask me where I get the ideas for my books and the answer is that they come from many different sources. Sometimes an idea is sparked by watching the news or reading the paper or a magazine. I read lots of magazines, everything from The New Yorker to People. The idea for BSC #84, Dawn and the School Spirit War, came from an article I read in a magazine.
Kids frequently send me plot ideas in their letters. I don’t use those specific ideas, but the letters are still helpful, because by reading them, I find out what issues are of concern to kids, or simply what they would like to read about in future BSC books. This was how the idea for BSC #93, Mary Anne and the Memory Garden, came about. Lots of books have been based on things that actually happened to me or to people I know. Some baby-sitting episodes are about things that happened to me when I was a sitter. My own baby-sitting memories gave me the idea for BSC #2, Claudia and the Phantom Phone Calls. For me, the best story ideas come from real life. This is why when kids ask for writing tips, I always recommend that they keep a journal — not so much for writing practice, but as a source of ideas.