The Sisterhood of the Traveling Pants

The Sisterhood of the Traveling Pants is a series of books by Ann Brashares. The series chronicles the lives of four girls who have been best friends since they were babies. One summer before they had to split for the summer, they find a pair of jeans that magically fit all four of them. So they decide to rotate the pants around through the mail to keep in touch while they're apart. Each book in the series takes place over one summer.

In 2005 a movie was made based on the first book. It starred Amber Tamblyn, America Ferrera, Blake Lively, and Alexis Bledel. The original series consisted of four books, but a sequel has been released since then, as well as a spin-off taking place in the same universe and focusing on new characters.

This series provides examples of:

 * Aesop Amnesia: Very weirdly averted. At first, Carmen getting mad at her mother for  might seem like she's forgetting her experiences in the first and second book, but her inner narrative states that she can figure out what happens when she gets angry and the fallout, but she still does it.
 * Played straight for almost everyone in
 * Anguished Declaration of Love: Lena gives two of these to Kostos.
 * Attractiveness Isolation: Lena
 * The Baby Trap: In the second book,
 * Blood Sisters: The girls practically consider themselves family being born around the same time and basically spending their entire lives together. It's in the title, man!
 * Calling the Old Man Out: Carmen does this to her father in the first book.
 * Character Development: A lot over the books, Bridget possibly receiving the most.
 * Chick Lit
 * Childhood Friend Romance: Bridget and Billy Kline in the second book.
 * Dead Guy Junior:
 * Dead Little Sister:  acts as one to   even though they were not related.
 * Deadpan Snarker: Tibby.
 * Did They or Didn't They: It's purposely left ambiguous if, though
 * Disappeared Dad: Carmen's father was one before the start of the series.
 * Disposable Fiance: Kostos has one in the original series and Carmen has one in the sequel. Both
 * Driven to Suicide: Implied with Bridget's mother.
 * Averted with
 * Epigraph: Each chapter begins with one.
 * Everyone Loves Blondes: Wild and unstoppable Bridget
 * False Friend: Julia to Carmen in the fourth book.
 * Family Business: Lena's grandparent's run a Greek restaurant together.
 * Four Girl Ensemble: Tibby, Lena, Carmen, and Bridget. 'Nuff said.
 * Four Temperament Ensemble:
 * Sanguine: Bridget.
 * Choleric: Carmen.
 * Melancholic: Lena.
 * Phlegmatic: Tibby.
 * Friendship Moment: Especially the endings of the books are full of them.
 * Good Girls Avoid Abortion: Played straight with
 * Hair of Gold Everyone Loves Blondes: Bridget's most striking feature, so  in the second book, it's clear something's up.
 * He Is All Grown Up: Brian by the third book.
 * Heroic BSOD: The entire year between the first and second book serves as one for Bridget.
 * Hey, it's that girl!: Serena van der Woodsen, Joan Ghirardi, Rory Gilmore, and Betty.
 * Not to mention Aria Montgomery.
 * Hippie Parents: How Tibby's parents were before they settled down and had more kids.
 * Ivy League for Everyone: Subverted in the third and fourth books. Bridget went to Brown, but the rest of the girls went to some prestigious schools outside of the ivy league.
 * Kuudere: Tibby (following the cynic route) and Lena (following the stoic and distant variety), both balancing Tsundere Carmen and Genki Girl Bridget.
 * Littlest Cancer Patient:
 * Lamaze Class: In the third book, Carmen goes with her mom to Lamaze class, but it's who's there when she gives birth.
 * Missing Mom: Bridget's mom died sometime before the series begins. It's implied to have been suicide.
 * Mood Swinger: Bridget. A popular Alternate Character Interpretation is that she has bipolar disorder.
 * Naked First Impression: Lena and Kostos.
 * Raised By Grandparents: Kostos.
 * Sex Changes Everything: Tibby and Brian in the fourth book.
 * And Bridget with Eric in the first.
 * Sibling Yin Yang: Lena is quiet and withdrawn, while her sister Effie is confident and outgoing.
 * So Beautiful Its a Curse: Lena, though in a more realistic case than usual. Her striking good looks contrast with her antisocial personality, and most people are too intimidated to even approach her.
 * Tsundere: Carmen, although she rarely is Tsun to any of her romantic interests, instead towards her family and occasionally her friends.
 * Wise Beyond Their Years: Bailey.