This book starts out with the girls getting into a huge fight. Mary Anne actually comes into her own in this book. While she's not my favorite of the baby-sitters, I do respect her, because she comes out of her shell. She even makes a new friend, Dawn, who becomes a member of the Baby-Sitters club at the end of the book.
Mary Anne also has to deal with a Baby-sitting emergency, which ends up not being so huge at all.