Lexie is the eldest daughter of Thatcher and Susan Grey and has a younger sister Molly. She is also the half sister of Meredith Grey, her father's daughter from a previous marriage. Lexie attended Harvard Medical School
Grey's Anatomy, Season 3Edit
Her mother Susan suddenly died when Lexie was just about to start her internship at Mass Gen and meets Derek in Joe's bar after her funeral and flirts with him. Lexie makes her first appearance in Seattle Grace when she introduces herself to George as one of the new interns. She has a one-night stand with Mark Sloan, sucking him up.
Grey's Anatomy, Season 4Edit
Lexie is assigned to surgical resident Cristina Yang for her year-long medical internship, and bears striking similarities to her half sister, Meredith Grey. She tries on several occasions to bond with Meredith, who wants nothing to do with her. Meredith sees Lexie's life as the one she could have had if her father hadn't left her and her mother, and thus has no desire to bond with her initially. Later, Meredith sits down with Lexie and explains the circumstances around her mother's death when Meredith was caring for her, suggesting they might kindle friendship as Meredith makes her first act of kindness. Lexie learns that George O'Malley is repeating his intern year and helps him keep the other interns unaware of his failure. She and George develop an unlikely friendship over intern struggles and their strained relationships with Meredith and Callie, respectively.
Lexie enters into a casual-sex relationship with Alex Karev, which causes conflict between her and Meredith but eventually leads them to work through their issues with each other, and Meredith's discovery that their father Thatcher is an alcholic, a secret harbored by Lexie, serves as a catalyst. After Lexie learns that Alex is still in love with Ava and a patient dies in her care Meredith allows her to stay over the following night and decides to try to repair their relationship, making Lexie breakfast the next morning. She and Meredith try to maintain a good relationship afterwards with them both starting to truly see the other as sister.
Her friendship with George leads her to move in with him into their own apartment. Lexie's relationship with her teacher Cristina also evolves after her ex boyfriend Burke wins the Harper Avery and takes her anger out on Lexie. Cristina's attitude towards her causes Lexie to think Meredith is taking her side and she confronts her sister, saying that Meredith has let her down, but the two seem to get back on track soon enough. Her relationship with George also develops as he kisses her after her actions lead to him getting to retake his intern exam, indicating that Lexie has deeper feelings for him.
Grey's Anatomy, Season 5Edit
Lexie's crush on George develops and she helps him pass his intern exam after he is granted a second chance. He eventually sucseeds and, when he is offered his own interns, Lexie is devestated when he doesn't choose her making her realize her feelings are one-sided. She is initally hostile towards George but eventually forgives him and tries to move past her crush. Tired of not being taught by Cristina and the rest of the residents, Lexie and the rest of the interns look for alterative ways to learn and eventually create an underground teaching club where they perform procedures on eachother. Cristina discovers this and shuts it down but after the arrival of Sadie Harris things take a dramatic turn. Lexie is forced to turn to Meredith and Cristina for help after the intern's attempt to remove Sadie's appendix goes horribly wrong. Derek then offers her a room at Meredith's house and he and Meredith start to look after her, firstly by insisting that Mark doesn't try and sleep with her. Mark manages to resist, in spite of their flirtatious relationship, until Lexie shows up at his hotel room and they sleep together.
Mark insists that sleeping with Lexie was a mistake but the eventually develop a relationship, which they keep secret from their colleagues. After Lexie refuses to treat Mark as her boyfriend until he makes it public, coupled with encouragement from Addison, he tells Derek but this results in a physical fight between the two. Lexie struggles when Mark and Derek refuse to talk to eachother and pushes for a reconsiliation between the two. The strain however pushes her closer to Meredith. Soon later her father returns, now sober, and unlike Meredith she chooses to forgive him. Lexie then asks Mark to meet her dad but he resists but eventually agrees to meet Thatcher, cementing their relationship as he does his first duty as her boyfriend. Mark then decides to buy a house, and asks Lexie to move in with him, but she turns down his proposition because she doesn't think they're ready for that. Mark decides to buy the apartment anyway to prove to Lexie that he's moving on.
Grey's Anatomy, Season 6Edit
Lexie is devestated by the death of George and she eventually agrees to move in with Mark, while trying to overcome her grief. She also finishes her internship making her a resident alongside her half-sister. Lexie also faces a devestating blow when Thatcher arrives in the hospital needing a liver transplant and must turn to Meredith for help when she is unable to provide a liver while Meredith is. Meredith eventually agrees to the procedure, but only for Lexie's benefit claiming that if Lexie lost Thatcher it would break her.
When the merger is announced, Lexie becomes paranoid about her future employment but eventually learns that she isn't being fired at the expense of the vast majority of her class. When the Mercy West doctors arrive Lexie is at the heart of the conflict but manages to keep her job, at the expense of other residents. She also develops a friendly rivarly with Mercy West doctor April Kepner.
She and Mark are shaken by the arrival of his pregnant, illegetimate daughter Sloan who begins to impose on their life and their relationship. When Mark asks Lexie to raise the baby with him and Sloan she breaks up with him, realizing she isn't ready for a family and the life Mark wants. Out of grief over her break up, she colors her hair blonde and sleeps with Alex and they resume their sexual relationship. Lexie remains clearly hung up on Mark, and is devastated when he starts dating Teddy, and insists she isn't developing feelings for Alex in spite of Meredith's concerns.
Lexie's fling with Alex slowly becomes more serious after he officially divorces Izzie and they begin a real relationship. However, just as she finds happiness with Alex, Mark makes a play for her after realizing he still loves her and suggests that he wants to marry her. Lexie is left torn between the two men in her life as the Seattle Grace Mercy West Shooting occurs. During the deadly scenario, Lexie and Mark try to save Alex's life after he was shot. As they await help, a delerious Alex mistakes Lexie for Izzie, revealing to his true feelings to Lexie, and Lexie tells Alex that she loves him to keep him holding on. After Alex is rescued, Mark tries to calm Lexie as she begins to struggle with the days events.
Grey's Anatomy, Season 7Edit
After the shooting, Lexie suffers a nervous breakdown while working in the E.R and Alex walks away, not able to handle it. Mark is forced to physically commit her to psych where she receives treatment for her breakdown, revealed to be a cause of her insomnia. She returns to work a week later, clear minded, and is cleared to return to surgery. After recovering, Lexie becomes hostile towards Alex and reminds him that he is alive because of her. Her return to work is clouded by other's judgments of her and she is forced to prove her capabilities. She also grows jealous of Meredith's friendship with April until she learns that Meredith was there for her constantly during her commitment. When Mark continues to try and protect her, she grows annoyed and fails to see the motivation behind his actions until April forces her to realize Mark still loves her. Her attempts at a reconciliation are thwarted when he sleeps with Amelia Shepherd, and Lexie tries to let go of the idea of them being together, developing a friendship with Jackson.
Mark pushes to reconcile but Lexie refuses, remaining clear that they are in different places, until he spontaneously kisses her reigniting their relationship. While there relationship got off to a good start, Lexie would soon face a devastating blow when she learned that Callie was pregnant with Mark's child. When her father arrives at the hospital sober and in a relationship with a younger woman, Lexie begins to feel as if all the men in her life are leaving her behind and, in a bid to start over, begins a relationship with Jackson after she sees potential in their flirtatious relationship.
Lexie and Jackson enjoy their honeymoon period but the reality of their situation soon comes to light after Callie's car accident forces Lexie to support Mark. In spite of this, she still chooses to go home with Jackson and promises that she's with him. After Mark's daughter is born, Lexie tries to push him to say goodbye to her given that, after all, they both got what they want and they agree to walk away from each other.
Grey's Anatomy, Season 8Edit
Lexie's relationship with Jackson continues and they seem happy together in spite of Mark and Jackson developing a mentor-mentee relationship which makes Lexie somewhat unnerved. However, her and Jackson face difficulties when Mark gets a new girlfriend, Julia. When a friendly softball match ends with Lexie lashing out at her, Jackson becomes aware that she isn't over Mark and subsequently ends their relationship, leaving Lexie alone while Mark grows steadily closer to his new girlfriend. After seeking advice from Derek, Lexie finally admits to Mark that she still loves him. In the last episode, Lexie is severely injured in the plane crash. As she dies, Mark confesses that he still loves her and that they were always supposed to end up together.
Lexie Grey is the oldest daughter of Thatcher Grey and Susan Grey (Thatcher's second wife). She has a younger sister, Molly, who is married with a child (born at Seattle Grace). Susan Grey is deceased from a rare case, death by hiccups. Meredith Grey is her half-sister, and therefore Derek Shepherd is her brother -in law. Zola is her niece and legal guardian if something were to happen to Meredith or Derek. Derek Bailey Shepherd and Ellis Shepherd, Meredith and Derek's other two children are her niece and nephew as well but aren't born until after her death in the plane crash.
Lexie Grey originally had feelings for George O'Malley, and then proceeded to get over him when she started to have feelings for Mark Sloan. Mark was swayed from a relationship as Derek Shepherd and Meredith Grey both agreed that it was inappropriate for him to be in a relationship with "Little Grey". They didn't form into a committed relationship for a long time after they first slept together. When Mark's daughter came to Seattle seeking help from Sloan (because she was pregnant), Lexie made the decision to end the relationship so that Mark didn't have to end it for them, she believed it was for the best in their relationship. Then, progressing, Lexie started sleeping with Alex Karev, and then Alex accidentally insulted "Little Grey" when he didn't mean to, and they ended the short-term relationship. However, she put her life on the line for him during the Hospital Shooting of the Season Six finale. They attempted reconciliation, but then Mark slept with Amelia Shepherd (Derek's younger surgeon sister), and so she gave up all attempts at the relationship; although she was still in love with him. Lexie agreed to start a relationship with Jackson Avery (which was originally a lot of sex and flirting rather than actual attraction and liking each other), and they where together for a while. When Callie was in the car crash, and Mark's baby was born; Lexie admitted her feelings for Mark and she and Jackson broke up soon after (when he realises that she will never love him the way Mark and Lexie love each other). During the await for rescuing after the plane crash at the end of season eight, when Lexie is dying, Mark admits that it will always be them, and that he will always love her. As Lexie dies, she holds Mark's hand, as she is half-trapped under the plane part. Mark then dies a few months later. He signed forms indicating that he wanted the machines turned off if there was was no sign of improvement for 30 days.
Lexie graduated from Harvard Medical School, and was set for an internship at Mass General Hospital, but her plans changed when her mother died of the hiccups at Seattle Grace, and she joined their internship program. she was in her surgical residency when she passed away of hemothorax during the plane crash.
- In addition to appearing in Grey's Anatomy, Lexie has also appeared in the Private Practice episode "You Break My Heart"
- Lexie was originally mentioned in the Season Two episode "The Name Of The Game" by Molly Grey when she talks about her family to their half sister Meredith.