The listing, The Babysitter's Club # 31 Dawn's Wicked Stepsister by Ann M. Martin has ended.
Now that Dawn and Mary Anne are friends and sisters, Dawn wants them to do everything together - share a room, talk all night long, wear each other's clothes.
But living with Mary Anne isn't exactly what Dawn expected. Mary Anne brags about having a date to the school dance, her kitten throws up on the rug, and she hogs Dawn's baby-sitting jobs!
Dawn's always wanted a sister. Instead, she got Mary Anne, the wicked stepsister of Stoneybrook!