Batty is having a hard time coming to grips with the passing of Hound. It just seems that her best friend is gone and in his place is the bratty little Miss Lydia. Duchess and Cilantro the dogs that make up her dog walking business adore her, but it isn't the same. At least she has her birthday to look forward to. Rosalind and Jeffery will be visiting, and Skye and Jane promise to put aside their bothersome teenage friends to pay attention to Batty on her special day. Batty has a surprise for all of them too, if she can keep it a secret. "But the best laid plans of mice and men often go awry" (John Steinbeck) and such is the case with Batty's birthday. This book is a part of The Penderwicks series.