The Cousins

Book review by
Lucinda Dyer, Common Sense Media
The Cousins Book Poster Image
Teens unlock a dark family secret in full-of-twists mystery.

Parents say

age 12+
Based on 1 review

Kids say

age 12+
Based on 4 reviews

Did we miss something on diversity?

Research shows a connection between kids' healthy self-esteem and positive portrayals in media. That's why we've added a new "Diverse Representations" section to our reviews that will be rolling out on an ongoing basis. You can help us help kids by suggesting a diversity update.

A lot or a little?

The parents' guide to what's in this book.

Educational Value

One secondary storyline focuses on a character's lifelong struggles with alcohol and shows readers the damage addiction can do not only to the person themselves but those around them. 

Positive Messages

Shows how teens who come from different backgrounds and may initially not even like each other, can learn to work together as a team to achieve a goal.

Positive Role Models

Milly's finding her own identity and her own way despite a mother who never compliments or touches her and is constantly telling Milly she's "on the cusp of mediocrity" if she doesn't bring her grades up. Aubrey's family's in crisis and she has a big decision to make. Her father's having an affair, her mother has moved out, and Aubrey has to decide whether to continue a relationship with her father. 


Someone is shot, and there are murders, mysterious deaths, and attempted murders. None of these events are graphically described.


Some kissing. A married character has an affair.


Characters regularly use strong language ("f--k," "—hole," "s--t," "bitch," "Jesus").


Teens eat PopTarts.

Drinking, Drugs & Smoking

Teens, college students, and adults drink and sometimes get drunk. One adult character is an alcoholic.

What parents need to know

Parents need to know that The Cousins, by Karen M. McManus (One of Us Is Lying), is all about family secrets. When the fabulously wealthy Mildred Story disinherited and cut off all contact with her four adult children, the only reason she gave was, "You know what you did." More than 20 years later, letters arrive inviting her three teen grandchildren to spend the summer working at her island resort in New England. But when the cousins arrive, they discover their grandmother hasn't invited them. Determined to find out the truth behind "You know what you did," the cousins discover imposters, coverups, and murder. There's strong language ("f—k," "a--hole," "s—t," "Jesus"), and teens drink and sometimes get drunk. One adult character is an alcoholic. While not graphically described, someone is shot and there are several murders and mysterious deaths.

User Reviews

  • Parents say
  • Kids say
Adult Written bymaia2200 April 12, 2021

fine but...

there is alot of cussing and dark stuff i liked the book just had alot of bad stuff to talk about in the book other wise great story and plot
Teen, 17 years old Written bySky Dawg November 9, 2021


The book is awesome. If you love a good thriller this is for you!
Teen, 15 years old Written byvolleyballplayer32 November 6, 2021

So Good!!!

This book is really good! I was able to predict a few of the things that were going to happen, but the ending was more of a twist than I was expecting! I was re... Continue reading

What's the story?

THE COUSINS is told in the voices of three teen cousins (Milly Story-Takahashi, Aubrey Story and Jason Story) and in flashbacks to 1996. The cousins all know that 24 years ago, their grandmother, Mildred Story, sent letters to her daughter and three sons, disinheriting them and cutting off all contact. The only reason she gave was, "You know what you did." But none of them did. So everyone is surprised when the cousins receive letters from their grandmother inviting them to spend the summer in New England, working at the summer resort she owns on Gull Cove Island. It's the opportunity their disinherited parents have been waiting for, so off the cousins are sent. The three barely know each other and seemingly have little in common. Milly is very much a big city girl from Manhattan, Aubrey is a competitive swimmer from Oregon, and Jonah appears to be a jerk from Rhode Island. But they do have one thing in common -- they're determined to find out what caused their grandmother to suddenly cut off their parents. Solving that mystery begins the moment they arrive, when they discover their grandmother never sent the letters and had no idea they were coming. 

Is it any good?

This is "never saw that coming" mystery is all wrapped up in complicated family dynamics, strained parent child relationships, and dark and deadly secrets. Some readers may initially be disappointed in leisurely start of The Cousins. But once the cousins arrive at Gull Cove Island, the speed of the story picks up and readers will have to pay really close attention to keep up with all the plot twists.

Talk to your kids about ...

  • Families can talk about the damage that keeping secrets causes in The Cousins. How do you decide when to keep a secret and when the right thing to do is to reveal that secret?

  • Have you ever wanted to assume someone else's identity? If you could be someone else for a day, who would it be?

  • What do you know about your family history? Are there any ancestors you'd like to know more about?

Book details

Our editors recommend

For kids who love mysteries and thrillers

Themes & Topics

Browse titles with similar subject matter.

Top advice and articles

Common Sense Media's unbiased ratings are created by expert reviewers and aren't influenced by the product's creators or by any of our funders, affiliates, or partners.

See how we rate

About these links

Common Sense Media, a nonprofit organization, earns a small affiliate fee from Amazon or iTunes when you use our links to make a purchase. Thank you for your support.

Read more

Our ratings are based on child development best practices. We display the minimum age for which content is developmentally appropriate. The star rating reflects overall quality.

Learn how we rate