Although the girls form their own close community, when they are in their own worlds apart from their friends, each struggles with being an outsider in some way. Carmen is an outsider in South Carolina because she is half Puerto Rican and her father and his new family are white. She stands out because of her dark skin, curvy figure, and Catholicism. Lydia, Krista, and Paul try to welcome her into their home, but they are initially surprised by her appearance. Tibby is an outsider among the friends, since she is the only one staying home this summer; among her family, since her parents are preoccupied with shopping and caring for her young siblings; and among the people at Wallman’s and in her hometown, since Tibby is well-educated and middle-class and many of the people she meets are not. Tibby assumes she is superior to this third group, taking pride in her outsider status. Lena is an outsider because of her extreme beauty. She immediately stands out in a crowd, and sometimes people assume they know things about her because of the way she looks. Bridget is an outsider in good ways (she is a stellar athlete and has gorgeous hair) and in not-so-good ways (her mother has died and she sometimes doesn’t know how to deal with her feelings).

All four girls must face their outsider status this summer and come to terms with it, either by struggling against it or by accepting it. Carmen struggles to figure out where she fits in her new family arrangement, and she must ultimately embrace her differences and do her best to get to know her new family. Tibby must step back from her proud outsider status and learn to accept, rather than judge, other people. She learns a lot from Bailey about being compassionate and kind. Lena can’t change the way she looks, but she does work on changing her reluctance to take risks and to be vulnerable. When she opens up to Kostos, she proves willing to show him what she’s like inside. Bridget isn’t so successful in quelling her aggressive soccer playing, and she either plays too hard or not hard enough. Also, she needs Lena’s help in coming up from her sadness, showing that even an outsider needs to reach out to her friends now and then.

With different body types, different interests, and different family backgrounds, the girls are indeed very different from one another. Whereas Bridget, Lena, and Tibby are white, Carmen is Hispanic. Carmen and Bridget enjoy sports; Lena and Tibby are artistic. Lena’s parents are together and Tibby’s are together but distracted, while Carmen and Bridget both live in one-parent households. Carmen is an only child, whereas the other girls have siblings. Tibby has an almost parental relationship with her brother and sister, since they are so much younger than she, and Bridget and her twin brother, Perry, don’t seem very close, while Lena and Effie are both sisters and friends. The girls have very different ways of dealing with problems, ranging from Carmen’s passionate outbursts to Lena’s quiet ruminations. Finally, the girls have different levels of self-awareness. Carmen thinks a lot about her friendships and how the future might change or not change them, whereas Bridget moves through life fast, rarely stopping to reflect on anything.

The girls’ differences strengthen their friendship, because their friendship is built on more than just common interests or similar personalities. The girls have known each other since birth—they like to think they were friends even before they were born. Having grown up together, the girls have developed a strong respect and love for one another as individuals, the kind of unconditional love that bonds parents to their children and siblings to one another. For them, it doesn’t matter who likes to do what, who dresses which way, or what shapes each girl’s life goals take. Because they know one another so intimately, they can celebrate one another’s triumphs and failures, heartbreaks and romances, and respect the very different viewpoints that color each individual girl’s experiences.

Throughout the summer, the Pants give the girls courage, support, and comfort and help them deal with the difficult situations they face. Because the girls are separated this summer, they can’t easily turn to one another for instant help, as they’re used to doing. Instead, the girls turn to the Pants, which serve a friendlike role when necessary. For example, Carmen turns to the Pants when she needs the courage to return to South Carolina and make things right with her father. Her friends don’t really know what she’s been through this summer, and she must do this difficult thing on her own. The Pants, however, make her feel less alone. Tibby must confront something very difficult: Bailey’s death. It’s easier for Tibby to ignore the really hard things, but the Pants, given to her by Carmen, help her get the courage she needs to reach out to Bailey when she needs to. Lena also gleans courage from the Pants when she decides to tell Kostos her true feelings. If her friends were there, they’d give her the courage to go forward. In their absence, the Pants make Lena feel brave. Bridget doesn’t need any more courage than she already has, but the Pants help her comfort her when she feels alone.

Ultimately, the Pants are a physical symbol of the girls’ friendship. The girls love and support one another through good times and bad, and they all have a deep trust that they will always be there for one another. This summer, this trust and belief were tested, since the friends were separated by distance for the first time. The Pants help them to realize that friendship doesn’t always require physical proximity. Even when the girls are apart, the love and loyalty that bond them stay as strong as ever. The girls believe the Pants help them through the summer, but what the girls are actually relying on is one another.