Family. A simple six-letter word. Yet somehow no one can ever figure out the exact definition. To most people, your family is your mother, father, siblings, aunts, uncles, cousin, etc. But what if those people aren't there for you? Are they still your family? Can people create their own families? Do some families just happen?

To Blair, Chuck, Nate, Serena, family means each other. The four Upper East Sidders are there for each other in good times and bad times. Serena holds Blair in her arms while the queen bee sobs after a binge and purge session. Chuck bails Nate out of an ill-fated poker game. Nate picks Serena up from whatever seedy bar she's been slinging back shots in and lets her cry without saying a word. Blair keeps Chuck together when his dad dies and it seems like his world is falling apart. They all stand by each other even if one of them is pushing the rest away. Because that's what families do. They fight for the people they love. And despite the jealousy, the fighting, and the heartbreak, the four are still family. The reasons why they believe in their little family, however, are varied.

Blair is a perfectionist, and she has been since she was a little girl. Eleanor used her as a model, dressing her up in frilly dresses with matching bows. Of course, one couldn't run or jump in these dresses. It was frowned upon. Instead, the small brunette learned how to sit up straight and keep her knees closed. It came to the point where Blair was always perfectly poised. If elegance was taught by her mother, ambition was taught by her father. Harold pushed her towards Yale before she could even write. She got her first Yale sweatshirt at three, went to her first Yale football game at five, and obsessed over her first Yale college brochure at seven. Blair molded herself into what she thought Yale would want and never looked back. Well, technically she did. Blair's most important lesson was learned in kindergarten, and it was taught by Chuck, Nate, and Serena.

On the first day of school, Blair was sitting up straight in a blue chair in her brand-new dress when a blonde-haired girl ran up to her. She was wearing a light blue shirt and worn jeans with mismatched socks that the other girl immediately noticed. There was something magnetizing about the blonde-haired girl, though. She introduced herself as Serena and asked if Blair wanted to jump on the trampoline with her. Since she was wearing a dress, Blair politely declined. Serena walked away sad. She approached a blonde-haired boy and asked him the same question. He replied yes, and the two held hands as they ran over to the trampoline. They motioned for Blair to join them, but she continued to shake her head no. A few minutes later, a dark-haired boy with a demeanor that seemed too old for him approached her and asked, "Scared?", with a smirk well beyond his years. He walked away and joined the other two on the trampoline. He kept looking over at her, however, with that obnoxious smirk. Fed up, Blair decided to ignore her mother's rules of etiquette. She threw her shoes off and got on the trampoline. The four children jumped until they collapsed in the trampoline in laughter. By the end of the day, Blair had made three best friends and learned her most important lesson: how not to be perfect.

And the three continued to teach her the same lesson as they grew up. Whenever Blair was freaking out over some small insignificant thing, Serena made her got out clubbing to relax and forget her worries. Whenever she got a little overbearing, Nate brought her back down to earth with a teasing comment. And on those days when it felt like her entire world was spinning at of control, Chuck kept her balanced. Blair knew she helped them too. She kept Serena from getting rapped after a hard night of partying and provided her some much need sense, made sure Nate was doing whatever he needed to do, and gave Chuck a purpose in his life. With them by her side, Blair didn't need to be perfect. She could just be Blair.

Most people called Chuck the devil, and for good reason. He wasn't exactly the guy you would want to bring home to meet the parents. So it isn't shocking to learn that most people don't think Chuck has a heart. Of course, those people are wrong. Chuck does have a compassionate side, but it only comes out when someone he cares about is in trouble. Most often, that group includes Blair, Nate, and Serena. They are the three people he has and will would do anything for. No one else would be able to compel Chuck to scheme against Georgina, give Blair her dream prom, and help Nate turn his dad in to the FBI. The three of them could convince him to do anything if he thought it would make them happier. Blair liked to tease her boyfriend about being a softie, which Chuck did not enjoy because you didn't tease a Bass. Growing up with a distant father made him eternally grateful for his friends. Without them, he really would be heartless.

Nate has come to hate other people's expectations of him. His dad wanted him to go to Dartmouth, his grandfather wanted him to go to Yale and become a senator, Vanessa wanted him to be less Upper East Side… The list went on. It seemed like the only people not demanding anything of him were Blair, Chuck, and Serena. Sure, Blair pushed him to do more and be better, but only because she knew he could do more and be better. That was his ex-girlfriend's way of showing she cared. Chuck gave Nate advice when he was being an idiot but never pushed him in any direction. Chuck's involvement meant either one of two things: 1). Blair convinced him to get involved, or 2). He genuinely cared about whatever was going on. Serena always turned to him when she was in trouble but never demanded he be her white knight. And the weird thing was that Nate liked his friend's expectations. He liked the fact that Blair thought he could do more, that Chuck thought highly enough of him to not need to push him in the right direction, and that Serena always came to him in times of crisis. The three Upper East Sidders didn't have any warped demands for him. They just wanted Nate to be Nate. That's why they were Nate's real family.

Serena has very few constants in her life. When her dad left, her mom started to bring men home trying to replace him, beginning the cycle of inconstancy that would haunt Serena for many years. She learned the cycle very quickly. Her mom would go out, meet a guy, go off for a while, maybe get married, come back with the guy, and break up with him within a month. The process would then start over again. Serena took over the mother role in Eric's life. He is one of her few constants. Still, something in Eric shocked Serena. It was his naivety. Every time, he thought their mom would be back for good, and each time her heart broke when he was disappointed. Serena searched for other constants. There was the doorman of her building, the open space of Central Park, and the flawless steps of the Met. As she got older, Serena tried to make her own constants. Drugs, sex, alcohol… It only took her a couple of years to realize that she had had three constants all along: Blair, Chuck, and Nate. No matter what, Serena knew that she could always count on Blair to hold her hair while she puked after a long night of drinking. Chuck would come over with food and bagels, and Nate would help Blair clean her up. And whenever she has bad news to tell them, Serena knew they'd still being sitting there when she was done talking. They are Serena's constants, and she knows she wouldn't have it any other way.