The Arnold twins aren't just bad — they're double the trouble!

Mallory and the Trouble with Twins
The Baby-Sitter's Club, # 21

Ann M. Martin

Cover Art

Hodges Soileau


February 1989, Scholastic



Kristy and the Walking Disaster


Jessi Ramsey, Pet-sitter

Mallory and the Trouble with Twins is the 21st book in the original The Baby-Sitter's Club series. Mallory sits for troublesome twins and her parents let her get her ears pierced.


Main PlotEdit

Sub PlotEdit

Back CoverEdit

Mallory knows she's a good baby-sitter. She's been looking after her seven younger brothers and sisters for years. So when Kristy offers her a steady job baby-sitting for the Arnold twins, Mal thinks it'll be easy money. The twins sure are cute in their little matching outfits. But once Mrs. Arnold leaves, Marilyn and Carolyn turn into twin terrors! They run around the house like spoiled brats, and Mallory can't even tell them apart. Taking care of Marilyn and Carolyn is a baby-sitting nightmare. But Mallory's a responsible member of the Baby-sitters Club--and she's not giving up!


References the book All Quiet on the Western Front.

Alternative CoversEdit

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