- This article is about the original novel. For the graphic novel, see Karen's Worst Day (Graphic Novel).
Karen's Worst Day is the third book of the Baby-Sitters Little Sister series.
Back Cover Summary
Karen is having a bad-luck day. Her favorite jeans are missing. There's no prize in the Crunch-O cereal box. And Boo-Boo the cat runs away from her!
Karen tries everything to make her day better. But her bad luck just won't go away. She even gets punished and sent to her room!
Poor Karen—will this be her worst day ever?
Characters in this book
- Karen Brewer
- Andrew Brewer
- Big House - Watson Brewer, Elizabeth Thomas-Brewer, Charlie Thomas, Sam Thomas, Kristy Thomas, David Michael Thomas
- Uncle Lou and Aunt Ann (mentioned)
Kids and Teens
- Hannie Papadakis and Linny Papadakis
- Amanda and Max Delaney
- John, Greg, Kate, Sandy (Charlie's high school friends)
- Tabitha Porter (Morbidda Destiny)
- Mr. Venta (mentioned)
- Mail Truck driver (not Mr. Venta the normal driver)
- Mr. Tastee
Places in this book
- Big House
- Papadakis Family house
- Sullivan's Sweets ice cream parlor
- The 2021 reprint was released July 6 2021,  with the spanish edition coming out on September 7, 2021 .
- This is the only book to mention Harry's Brook, where Linny and Hannie plan to go to catch minnows and crayfish.
- It's not mentioned which side of the family Uncle Lou and Aunt Ann are from; however, they are Andrew's godparents.
- Pop culture references include: Mr. Ed and The Secret of NIMH.