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Paperback BSC #21: Mallory and the Trouble with Twins Book

ISBN: 0590673890

ISBN13: 9780590673891

BSC #21: Mallory and the Trouble with Twins

(Book #21 in the The Baby-Sitters Club Series)

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Format: Paperback

Condition: Good

Almost Gone, Only 1 Left!

Book Overview

America's favorite series returns with a new look and a Netflix tv show.Mallory knows she's a good baby-sitter. She's been looking after her seven younger brothers and sisters for years. So when... This description may be from another edition of this product.

Customer Reviews

6 ratings

This book too was falling apart. Whole chapters fell out.

Story is good. This book too was falling apart. Whole chapters fell out.

One Of The Best!

When 11 year old Mallory baby sits for Marilyn and Carolyn Arnold, she thinks it's going to be okay. But when Mrs. Arnold leaves, the twins turn into horrible brats. Taking care of The Arnold Twins is a baby sitting nightmare. But Mallory's a responsible member of the BSC- and she's not giving up!

Good book

I read this book as a girl, and am sad to see it's out of print, but glad that I saved my copy. I've always found twins and large families fascinating, so this book was great. Mallory is from a large family and babysits twins, who turn out to be nightmares. I also loved to shop and they did that in the book. It was one of my favorites of the series.

Great book to read while relaxing.

I liked this book a lot. I keep it downstairs and read it while I am eating my cereal in the morning. Its about the Arnold twins, Carolyn and Marilyn who try to confuse Mallory and switch their identities. But the truth is, they don't like even dressing up like twins and stuff, they want to be their own seperate people which Mallory eventually discovers. So, this is a great book, enjoy!


The Arnold twins are new clients to the BSC. Mallory gets the job. But her job is a disaster! But soon, Mallory has to find out why the twins are acting so horrible. Mallory soon finds the answer, and she's trrying to help them through their terrible time.


This was my very first BSC book I read, which was maybe 4 or 5 years ago. It's very good. Mallory has recently been initiated into the BSC, and wants to prove to Kristy that she is a responsible, trustworthy sitter. So she takes a sitting job for the Arnold twins, thinking that it will be a peice of cake. She already has 7 other siblings. Simple, right? Wrong! The Arnold twins - Marilyn and Carlolyn- are distasters! They are identical, and drive Mal crazy! They hide from her, lie, get her in trouble, and switch their ID bracelets, so Mal can never tell who's who! Will Mal be able to prove to Kristy that she really is a good sitter, even with these two on her hands
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